Thursday, September 5, 2019

Biotechnology: Applications and Arguments For and Against

Biotechnology: Applications and Arguments For and Against The use of genetically modified organisms (GMOs) in agriculture is rising, but not without debate. There are many scientists who argue that genetic engineering in agriculture is the best way to solve many issues of poverty, food security, environmental harm, and the need for increasing competitiveness in sales, but others raise ethical issues regarding the health of the people who consume the genetically modified products, the possible harm to the environment, the depredation of the welfare of the farmers and their food security, and the general introduction of engineering into mainstream use in society. 1.2 Definition of Genetically Modified Organisms Genetically Modified Organisms, commonly called GMOs, refer to organisms whose genetic material has been altered using recombinant DNA technology, a method used to recombine the DNA of different organisms. 1.3 Sequence of Discussion I begin the paper with an introduction to the issues of using biotechnology and generating GMOs in agriculture. I continue with arguments both for and against the use of biotechnology in agriculture. I conclude the paper with information about the current debate on this issue and resources to obtain more information. 2.0 Prelude to the Issues The use of genetically modified organisms to enhance the production, yield, and quality of agriculture is under much discussion. Biotechnology companies are actively investigating the research and development of new technologies to improve food security and augment production of goods in both the developed and developing worlds, while activist groups work to ensure that biotechnology is not used in food production at all for fears of damage to the environment and human health, among other issues. On the other hand, according to Dr. Miguel Altieri, a leading spokesperson in the field, the view that GMOs can enhance food security in the developing world rests on two assumptions: that hunger is due to a gap between food production and human population density or growth rate and that genetic engineering is the best or only way to increase agricultural production and so meet future food needs.1 While it is clear that there are benefits to using biotechnology to improve crop production, th ere are also many fundamental and ethical arguments against its use, as is illustrated shortly. 3.0 The Argument for Biotechnology 3.1 Applications of Biotechnology to the Goal of Poverty Reduction Several objectives of using biotechnology in agriculture are associated with the reduction of poverty. Introducing GMOs into agriculture is predicted to increase rural incomes, sustain production in resource-poor areas, and provide more nutritious foods. Supporters of the use of biotechnology in food production believe that developed nations with technology have a social and political obligation to assist these poorer nations. In India, Vietnam, and Kenya, diseased vegetable crops and trees can benefit from genetically produced bio-pesticides. The cardamom crops in India, potato crops in Vietnam, and banana crops in Kenya are often farmers sole source of income, such that diseased crops can have an extremely damaging affect on the farmers lives. Problems with a lack of clean and pure seeds and planting material can be solved by using bio-pesticides, which allow for leniency in the purity of the seeds and planting material. In this way, GMOs can potentially provide a means for high-resistance and high-yielding crops.2 Biotechnology can also contribute to sustaining the production of foods, commonly cereals and maize, in resource-poor areas. Drought, pests, and acidic soil often cause detrimental problems to farming, but insect resistance and aluminum tolerance can circumvent these environmental barriers. The ability to provide a full farming season through using GMOs to assist in the production of larger quantities of food for these farmers helps to ensure a profitable growing and harvesting season.2 Finally, GMOs can contribute to generating more nutritious foods with higher nutrient content-this technology most commonly being applied to rice. The people in countries such as India and China rely heavily on rice in their diets, but rice alone does not provide the necessary nutrients for a balanced diet. 3.2 Applications of Biotechnology to the Goal of Financial Security for Farmers Farmers can make great use of transgenic techniques in their agriculture with the goals of both ensuring food security and increasing the competitiveness of their crops. Biotech companies and supporters of the use of GMOs believe that there exists a political obligation to assist in the security and well-being of farmers who supply goods to more developed countries. Food Security The biotechnology objectives in agriculture that are associated with issues of food security include meeting the demand predictions for staple foods, increasing livestock numbers, and increasing vegetable and fruit yields. Two major constraints that farmers encounter with regard to meeting the demand predictions for staple foods, which must be grown in large quantities, include the presence of pests and the consequential infectious diseases, and problems associated with biotic stress. Pests and disease are often a problem in rice crops in China, and the addition of genetically modified rice varieties with pesticides can assist in the prevention of diseases in these crops. In addition, GMOs are valuable for avoiding abiotic stresses, such as salinity and drought. In India, China, and Thailand, hydration and salinity tolerance in cereals, considered to be staple foods, assist in the security of high yields of these food crops to meet the demand.1 In India, biotechnology can help to avoid the major problem associated with the keeping of livestock, i.e., the probability of diseased animals, including cattle, pigs, and sheep. In addition, embryo technology can sidestep issues of productivity in dairy cattle. Both of these uses for GMOs lead to an increase in both livestock number and productivity.2 Biotechnology is also useful for securing a stable food supply by increasing vegetable and fruit production. Pests and diseases infect these crops, often completely depleting their production. Examples of crops are tomato and potato crops in Vietnam, as well as papaya crops, which can become infected with the ringspot virus.2 3.2.2 Increasing Competitiveness The use of biotechnology in agriculture can also assist farmers competitiveness on the global market, specifically by sustaining productivity exports, regulating food safety and quality control, and adding value to exports. Biotechnology is useful in sustaining exports by increasing the yield of crops, such as coconut crops in the Philippines, banana crops in countries such as India, China, and Vietnam, and potatoes, rice, maize, wheat, cassava, and beans in other developing countries.2 In addition, GMOs can contribute to food safety and quality control with respect to food exports by controlling pesticide residues and ensuring the competitive quality of exports.2 Improved quality can include characteristics such as texture, taste, appearance, and nutritional value, and the ability to delay the ripening of fruits and vegetables can greatly approve the longevity of some produce. Specific improvements for producers are an increased flexibility during production, harvesting, storage, distribution, and transport stages, leading to a reduction of overall production costs and a greater guarantee of quality product at the time of selling.3 3.3 Applications of Biotechnology to the Goal of Environmental Protection The introduction of technology into the environment can be hazardous and brings up ethical issues associated with protecting the environment through the use of technology (also see section 4.2). However, many supporters of GMOs claim that biotechnology in agriculture can enhance protection of the environment, specifically by reducing pesticide use and enabling the efficient use of water. Pesticide misuse on cotton and rice crops in China and on vegetables in Malaysia is a common problem when farmers are misinformed of use of pesticides, or when pesticides are overused in attempt to deter crop failure due to pests. Transgenic crops can potentially reduce the need for and usage of pesticides by assisting pest extermination and preventing weed growth. GMOs such as Bacillis thuringiensis (Bt), a natural soil bacterium, can be used to kill insects by allowing the plants to produce their own toxin against pests, sidestepping the problem of farmers who are mis- and overusing pesticides. In addition, herbicide tolerant crops ideally require fewer herbicide applications, because the crop is genetically programmed to more efficiently utilize the particular chemical product.4 Finally, transgenic herbicides can be applied to pre-treat the land, so that weeds are altogether prevented, and farmers can weight the options and costs of using more chemicals versus dealing with weed gr owth during harvest.3 4.0 The Argument Against Biotechnology 4.1 Uncertainty of the Safety of Humans After Consumption Although there is a lot of anticipation and excitement about the beneficial effects that can potentially result from the use of biotechnology in agriculture, there is also a lot that is unknown about the uses of transgenics and their impending consequences. Specifically, examples of these issues include the lack of available public information and knowledge about the content and effects of GM foods, the possible inactivation of many nutrients present in naturally-grown foods, and the introduction of allergens through the use of GMOs. These are all social, ethical, and legal issues based on the morality of tampering with foods in a way that will have an unknown effect on human health. As just stated, one major issue regarding the allowance of the free use of GMOs in agriculture is associated with the unknown potential health effects of consuming chemically treated foods. Consumers assume that the foods they buy are safe, even though many contain compounds that are potentially toxic or allergenic. The general public has a large misunderstanding about genetically modified (GM) foods because companies do not boldly advertise their use of transgenic components in their products. For this reason, people often consume GM foods without even knowing it. In addition, while many biotechnology companies advertise the use of transgenics in agriculture as beneficial to human health by improving the nutritional content of food, genetic engineering also has the potential to remove or deactivate many nutritional substances present in naturally-grown foods: Recent research shows that GE [(genetically engineered)] herbicide resistant soybean have lower levels (12-14 percent) of isoflavones, [which are] key phytoestrogens . . . that occur naturally in soybeans and may protect women from severe forms of cancer.1 These genetic modifications boost the activity of a gene that makes critical amino acids, but the resulting shift in amino acid levels shifts the metabolism of the plant to alter the levels of the aforementioned phytoestrogens. This effect is clearly seen in GM soybeans, even when the chemical residue data is within the Environmental Protection Agency (EPA) tolerance limits.4 Finally, the use of GMOs in agriculture brings to question the compromise of human safety because of wide Finally, the use of GMOs in agriculture brings to question the compromise of human safety because of wide reports of increased allergenicity after consumption of GM foods. For example, a protein was expressed in a crop used for animal feed in order to increase the content of the amino acid methionine. This protein was subsequently shown to be an allergen, as are a number of related [proteins of this type] from other species.5 Another example of the use of biotechnology introducing an allergen into a food product is the use of a Bt protein in GM maize, which also shows the general features of allergenic proteins.6 These are simply two examples of how the application of biotechnology can introduce allergens into crops. Since research is still just beginning on many GMOs, the allergenic effects of the use of biotechnology in agriculture remains unclear and under investigation. Antibiotic resistance is the ability of a bacterium or microorganism to withstand the use of an antibiotic because of its ability to synthesize a protein that neutralizes the antibiotic.7 While it is thought that the use of genetically engineered pesticides and herbicides on crops might only have the effect of reducing pests and weeds, it can actually have an opposing effect as well. The generation of superbugs and superweeds, pests and weeds resistant to the GM pesticides and herbicides, respectively, can result. Not only can the crops that are sprayed acquire these characteristics, but hybrid crops can arise when crops cross. This can cause resistance in crops that were not previously sprayed with GMOs, and can also cause multi-tolerant crops when two crops that are sprayed with different chemicals cross. The result of this second cross is a crop that is resistant to multiple herbicides (i.e., superweeds) or pesticides (i.e., superbugs), which are even more difficult to control. In addition, this resistance can give these weeds and bugs a selective advantage over the naturally-tolerant weeds and bugs, allowing them to propagate efficiently.5 5.0 Conclusions While there are many points both in favor and against the use of GMOs in agriculture, some people believe that the question simply comes down to whether or not it is ethical to engineer in agriculture, which has always been managed by farmers themselves in conjunction with local biological cycles and ecological balances. Activists against the use of technology worry about future generations, and how the use of biotechnology in agriculture now will affect food production in years to come. They raise concerns that regulations are too loose and poorly enforced, and the eventual effects of the use of GMOs remain unknown. In addition, important issues revolve around whether or not it is ethical for well-fed people of developed nations to regulate access to agricultural technology in developing nations. According to Dr. Altieri, because the true root cause of hunger is inequality, any method of boosting food production that deepens inequality will fail to reduce hunger. Conversely, only te chnologies that have positive effects on the distribution of wealth, income, and assets, that are pro-poor, can truly reduce hunger.1 Therefore, questions regarding the use of biotechnology in agriculture should better address the needs of poorer nations. Many people are still under-informed about potential benefits and negative effects of using GMOs in agriculture, and are therefore not ready to form an opinion on the issue. For this reason, there are many forums on the internet and published books to help interested people learn more. In addition, several documentaries present these issues, an example being The Future of Food, a documentary by Deborah Koons.9 The issues regarding the use of biotechnology in agriculture are important and affect everyone, and should not be overlooked. People in favor of the use of biotechnology in agriculture argue that it is unethical not to help poorer nations when more developed nations have the technology to do so. On the other hand, activists against the use of GMOs in agriculture maintain that more harm than good comes from the introduction of GMs into food production. How does Culture Affect Parenting Styles? How does Culture Affect Parenting Styles? A family is a set of intimate social relationships that adults create to share resources so as to ensure the welfare of themselves and their dependents (Robert and Lie 77); a family is also a unit that gradually molds a persons personality. How you behave and what you become in life are very much dependent on your family life (Importance). To this extent, families play crucial role for people in their lifetime, let alone for children whose social interaction begins at first between family members. Researchers have demonstrated time and time again that the environment in which children are raised significantly affects their intellectual, physical, social, and emotional development (Important). They further emphasize that those impacts on their childhood will probably be carried on even after they grow up and experience a lot of changes. For decades, researchers have also been interested in how parents influence their childrens development, and one approach in this area is the study of what has been termed as parenting style (Darling and Steinberg 493). This paper is a review of research studies on parenting styles within the ethnical (cultural) contexts. The idea of examining this field of study is partially derived from Chapter 2 (Culture), Chapter 7 (Race and Ethnicity) and Chapter 9 (Family) in the book named Sociology: The Points of the Compass, written by Robert Brym and John Lie. The whole paper is divided into several sections. First, it starts with the illustration of ethnical (cultural) aspects that differentiate families. It is then followed by the classification of parenting. The paper then focus on the influence of culture on parenting styles and finally provides a conclusion as a whole. Families Are Different Family define themselves as a family. Membership in a family can be decided only by each member of that family (Couchenour and Chrisman 22). Families differ from one another in many ways; ethnicity and culture are two crucial differences greatly impact on a familys beliefs, practices, and values (McGoldrick, Giordano and Garcia-Preto 1). Ethnicity Ethnicity is a shared concept and culture heritage by groups of people whose commonality are transmitted from their ancestors generation by generation (Couchenour and Chrisman 22). The identity of these ethnic groups is uniquely marked based on the combination of race, religion, traditions, and ancestors (Robert and Lie 302). They differ from others in terms of languages, foods, stories, customs, values, and other aspects. Families carry on their ethnicities through their own family traditions, celebrations, religions, stories, and entertainments (McGoldrick, Giordano and Garcia-Preto 14). The importance of ethnicity on each family varies (Couchenour and Chrisman 23). Culture Culture is the unique experiences of ethnic groups using languages, symbols, beliefs, values, ideologies, and material objects to deal with real-life problems (Robert and Lie 40). It acts to shape familys values, thoughts, reactions and socialization goals (Bigner 8). Therefore, the styles of communication between parents and children can be quite different among various cultures, which means what is considered to be an acceptable way of interaction in one culture could be very offensive in another cultural context. When parents are exposed to a dominant given culture with high frequency, they are affected by the norms and values of that culture (Keshavarz and Baharudin 67). Consequently, those culturally affected norms and values could easily serve as the guidelines for parents to interact with their children. In this sense, understanding the cultural context of the society can potentially help to predict differences parenting styles that predominate in that society and to understan d why these differences occur (Keshavarz and Baharudin 67). Trawick-Smith states, Only through a full understanding of parental beliefs, socialization practices, and family relationships, can the individual needs of individual children be well met (qtd. in Couchenour and Chrisman 25). The Classification of Parenting Styles The principal role of parenting involves the promotion of nurturing, balanced relationships or, contrastingly, the exacerbation of stress-prone, hostile exchanges between parents and children (qtd. in Keshavarz and Baharudin 67). Darling and Steinberg emphasize that parenting style is a constellation of attitudes towards the child that are communicated to the child and create an emotional climate in which the parents behaviors are expressed (493). Baumrind has investigated parenting styles in a series of studies and found three primary categories of parenting styles identified as authoritative, authoritarian and permissive (Reeves), which later on are conceptually expanded by with two linear constructs: responsiveness and demandingness (qtd. in Sonnek 8). Authoritative Parenting Referring to those studies conducted by Baumrind, authoritative parents are conscientious, consistent, warm secure in their ability to parent and unconditionally committed to their children (Reeves). On one hand, they state behavioral expectations to children; on the other hand, they respect their childrens opinions and independence; while setting high but realistic goals for their children, they also provide the necessary supports for them to achieve these goals. The authoritative parenting was found most effective in fostering social responsibility, sense of self-esteem, confidence and adaptability in their children to meet challenges of academic and other contexts where strong beliefs in ones abilities are required (Couchenour and Chrisman 94). Some researchers have examined the relationship between parenting style and childrens adjustment, and confirmed that authoritative parenting style is positively associated with healthy adjustment and reducing maladjustment than other styles of parenting (qtd. in Keshavarz and Baharudin 67). Authoritarian Parenting Authoritarian parents provide firm and high control over their children and require them to be very responsive to their demands; they are very punitive and affectively cold; they set firm goals to their children but allow little verbal exchange; compared with two other parenting styles, authoritarian parents are less likely to use gentle methods of persuasion (Reeves). To this extent, children have poor communication skills, and social incompetence; they are easily to become anxious while being compared with others. Studies on the relationship between parenting style and childrens adjustment have found that children of authoritarian parents tend to have low self-esteem and lack spontaneity (qtd. in Keshavarz and Baharudin 68). Permissive Parenting Characteristics of permissive parents are identified as warm, high nurturance, responsive but low in parental control and demand few maturity behaviors (Reeves). Permissive parents would like to allow their children to control their activities as their willingness. They expect little of children, and place few demands on them. This parenting style tends to be unsuccessful in enabling children to develop a range of self-directing abilities that underlie academic success (qtd. in Keshavarz and Baharudin 68). Researches later on split the permissive parenting style into a fourth category- indulgent and neglecting parenting, which most fits with its definition (qtd. in Sonnek 8). Cultural Influences on Parenting Styles In the nineteenth century, parenting experiences varied considerably by gender, age, social class, and culture, just as they do today (Baker 94). Individuals may consider parenthood as fulfilling a moral obligation (Bigner 9). Vygotsky indicates that human knowledge is rooted in culture (qtd. in Couchenour and Chrisman 8), which means what much of what children know derives from their families, such as, how to celebrate holidays; how to prepare, cook and eat foods; and how to behave properly in the public places. On many occasions, childrens behaviors of are mostly based on their parents expectations and demands. The values and ideals of a culture are transmitted to the next generation through child-rearing practices (Keshavarz and Baharudin 68). Therefore, children in different cultural contexts can be cultivated by their parents to behave differently; in this sense, it is necessary to take into consideration the importance of culture when evaluating parenting behaviors. Cultural models of individualism and collectivism can bring direct as well as indirect impacts on parenting behaviors (Keshavarz and Baharudin 68). Its direct influence on parenting behavior could be explained by passing on values of a culture to their children to become productive and integrated members of their culture (qtd. in Keshavarz and Baharudin 68); its indirect influences on parenting behavior are via more societal forces such as language patterns and customs, and economic structure indirectly (Health Canada 8). To this extent, parents can relate their parenting with those direct and indirect cultural effects. Individualism and collectivism refers to the manner in which people perceive themselves in relation to other members in the society (Brislin 23). Literally, individualism indicates independence. It includes the wide-spread and growing belief that people have the right to choose their own martial partners, to be happy in marriage, and to find new partners if their relationships turn out to be unsatisfactory (Baker 24). In contrast, collectivism implies interdependence. It includes the mutual emotions and beliefs shared by people as a result of living together (Robert and Lie 371). Robert and Lie further explain that collective actions include routine actions and non-routine ones, which take place when people act simultaneously in accordance with or opposition to external changes, such as social, political, economic, etc; their difference is that the former ones are typically nonviolent and follow established patterns of behavior in existing social structures, whereas the latter ones o ccur when usual conventions cease to guide social action and people transcend, bypass, or subvert established institutional pat ­terns and structures (371). In this sense, different family relationships, family interactions, self-concept, and academic achievement can be assumed via collectivism and individualism (Newman 51). Therefore, the arrangement of childrens activities differs from parents to parents with differing childrearing goals and cultural meaning systems (Keshavarz and Baharudin 67). Collectivism can be fully reflected by most Asian countries. Parents emphasize desirable traits such as interdependence, duty, sacrifice, compromise, conformity, highly involvement in one anothers lives, however, it does not mean a complete ignorance of individuals well-being or interest; it actually means that maintaining the familys well-being is ultimately the best guarantee for the individuals well-being (Newman 51). To this extent, authoritarian parenting may be more appropriate in those collectivistic societies compared with other parenting styles (Keshavarz and Baharudin 69). High levels of economic hardship have been greatly linked with authoritarian parenting and even neglecting parenting -a split of permissive parenting (qtd. in Sonnek 16). In sharp contrast, cultures like Western Europe, the United States, Canada, and Australia tend to value individual freedom, autonomy, personal development, and gratification over group obligation and duty (Newman 52); Newman emphasizes that childhood is sometimes regarded as the preparation for leaving home as the sign of independence, even those people who experience unwillingness and sadness at the thought of breaking these ties accept that it is a necessary step towards growing up (52). Therefore, it could be concluded that it is much more appropriate to examine parenting styles and their meanings in the cultural context (Bigner 9). In the conceptualization, culture is theorized to afford different meaning to behaviors (e.g., parenting) and has different effects on children and adolescents across different cultures (Keshavarz and Baharudin 69). For instance, in China, where I was born and brought up, proper and mild physical punishments are sometimes used by parents for controlling their children; they are considered as part of the authoritarian parenting; however, this parenting style is greatly opposed by many other cultures, and regarded unacceptable. Researchers mention that children will accept parenting behaviors which are consistent with cultural values (qtd.Keshavarz and Baharudin 69). For example, Chinese kids (including me when I was young) view spanking, which could be one of the physical punishment, as their parents concerns and affections on them in the Chinese culture. Conclusion Chapter 9 of Sociology: The Points of the Compass concludes that Parenting styles and behaviors perform a crucial role in the growth of children. Ethnicity, described in Chapter 7, is a socially constructed label which has profound consequences for peoples lives, and differentiates people by perceived physical or cultural differences (Robert and Lie 198); these cultural or ethnical differences can lead to different parental forms and behaviors in different social context; in other words, the ways that family members interact with each other are affected by the culture of the society, therefore, just as what has been examined in Chapter 2, what counts as good for raising children in one culture can be regarded as negative in another culture; to this extent, cultural and ethnical factors should be counted in order to better understand and examine parenting styles in different societies. Cri-Du-Chat Syndrome: Symptoms and Causes Cri-Du-Chat Syndrome: Symptoms and Causes Cri-Du-Chat Syndrome Introduction Cri-du-chat is an autosomal syndrome that is caused by a large or small deletion from a portion of the short arm of chromosome. This syndrome is also known as the 5p deletion syndrome where the P describes the short hand chromosome and Lejeunes syndrome. It is also called cat cry syndrome which is a French translation of Cri-du-chat, because of its similarity to the high pitched cat cry like sound a new born child makes. This sound is supposed to disappear a few weeks after birth and may or may not persists in to adulthood. In 1958 Dr. Jerome Lejeune discovered down syndrome. He discovered that the chromosomal link to down syndrome. This discovery was ground breaking for discoveries in genetics because it was the first time that an intellectual disability and a chromosomal defect were linked together and this earned him multiple prestigious awards. Up on continuing his research on chromosomal liked disorders, he also discovered that down syndrome was caused by an extra chromosome on pare 21 and he also noticed a deletion on the 5th chromosome which is the cause for Cri-du-chat syndrome. (1) Symptoms and OMIM Number Cri- du- chat The relationship of chromosomal alteration and genetic disease was observed that the main clinical feature was the high pitched cry and hindered mental capacity (Mainardi, 2006). The OMIM number for this syndrome is # 123450. The number sign is used to indicate that it is a well described partial aneusomy. Syndrome causes many phenotypical changes which depend on the size of the deletion. Some or all of the symptoms might be present in a patient. It has also been found that the deletion of the telomerase reverse transcriptase gene (TERT; 187270) well as evidence that deletion of the telomerase reverse transcriptase gene (TERT; 187270) is present which is also responsible for some of the phenotypical changes. (2) Besides the high pitched cry, Cri-du-chat is characterized by failure to thrive, broad nasal bridge, round moon shaped face with hypertelorism, Anisocoria, undersized jaw and heads , depleted motor senses hypertonia, small carpals, low birth weight and incomplete intestinal r otation in infants. There are some less distinctive symptoms such as separation of rectus and abdomen, cardiac abnormalities including atrial and ventricular septum defects, primary immunodeficiency, an epicanthal fold which covers the inner corned of the eye and inguinal hernia. (Chromosome 5, 2017).) Once the infant is born there is a low mortality rate until adulthood where most of the symptoms observed as a child continue on with addition of misalignment of teeth, skeletal problems, eye defects and in some cases neurological malformation, Syndactyly, undescended testis in male patients, and skin tags on the ear occur. (Mainardi, 2006,) Clinical causes of symptoms The syndrome is caused by a deletion of the short arm, which is also denoted by P, of chromosome 5. Chromosome 5 contains more than 900 genes that code for specific proteins such as interleukins, protocadherins and complement proteins. The function of these proteins range from regulation of immune system, nervous system controls and muscle formation and strength. The deletion of Some Sections of chromosome 5 such as 5p15.3, specifically at markers D5S731 and D5S760, are directly associated with the cat like cry and speech delay. Another region called 5p15.2, specifically CTNND2, is related to lower intellectual ability, and dysmorphism of head size and facial features. The severity of mental and motor capacities can depend up on the size of the chromosomal deletion (Chromosome 5, 2017). Although the affected family members apparently shared deletions of the same size, the variation in mental symptoms within this family suggested that other factors besides the size and location of 5p deletions may modify the mental presentation of patients with cri-du-chat syndromeThey suggested that a cranial developmental field, originating from the notochordal location, is involved in the manifestations of criduchat syndromehowever, the characteristic cat-like cry without the typical dysmorphic and severe developmental features of the syndrome has been found in individuals with a deletion confined to 5p15.3The cranial base angle was in most cases reduced and in no cases increased compared to age-related standards for normal individuals. Malformations in the bony contours of the sella turcica and the clivus occurred in cri-du-chat patients with terminal deletions. Frequency The frequency of the disease is 1:15000 to 1: 50000 of new born infants. Cri-du-chat makes up 1% of profoundly retarded patients who have IQ levels that are less than 30. Since it is a genetic deletion it doesnt have a preference as far as race nut it has a slight female dominance ratio of 4:3. This syndrome doesnt have a latency, the symptoms are present starting from birth and continue to show the symptoms in to adulthood. In most cases it has been seen that the symptoms become more severe in to adulthood. (Harvard et al., 2005, pp. 341-51). Inheritance pattern Cru de chat is not an inherited syndrome. It is a random deletion that occurs during meiosis and can occur without the parents being affected. However close to 10% of the affected individuals can inherit a chromosomal abnormality from unaffected parents. This abnormality is caused by chromosomal rearrangement called Balanced Translocation where the genetic material is still intact and doesnt cause any health problems. However when this trait is passed down from one or two parents it has a high chance of becoming and Unbalanced Translocation which can cause a genetic material to be added or deleted. In the case of cri du chat the short arm of chromosome 5 experiences a large or a small portion deletion which causes the syndrome. In some cases the catlike cry can be present without the physical abnormalities. This is more evident in the deletion at a specific location in the chromosome 5p15.3. Malformation in the cranial base was reduced and compared to a standard individual it doesnt show a major difference. However malformations in the contours the skull such as in Sella Turcica occur in patients that have terminal deletions. In one of the studies conducted with in the same family showed different symptoms and levels of mental retardation even though they shared the same size deletion. This suggests that not only the size but the location of deletion affects the severity of the syndrome (2) References Cerruti Mainardi, P. (2006). Cri du Chat syndrome. Orphanet Journal of Rare Diseases, 1, 33. Chromosome 5. (2017, January 24). Retrieved January 29, 2017, from U.S National Library of  Medicine. U.S department of health human services website: Chromosome 5. (2017, January 24). Retrieved January 29, 2017, from U.S National Library of  Medicine. U.S department of health human services website: Harvard, C., Malenfant, P., Koochek, M., Creighton, S., Mickelson, E., Holden, J. Rajcan-Separovic, E.  (2005). A variant Cri du Chat phenotype and autism spectrum disorder in a subject with de novo cryptic microdeletions involving 5p15.2 and 3p24.3-25 detected using whole genomic array CGH. Clinical Genetics, 67(4). j.1399-0004.2005.00406.x (1) (2)

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