|MadSci Network: Genetics|
I am sorry to say that your parents may have misunderstood the genetic explaination of the disease. A recessive allele never takes over a dominant allele. Cerebral Palsy, however, is mostly caused by infection, stroke (due to many rasons, such as abnormal blood cells),oxygen loss during pregnancy or child birth, jaundice, and Rh incompatibility. Thus Cerebral palsy seems to have no direct genetic component, however there can be an indirect genetic component such as the abnormal blood cells mentioned above. To talk about Anglemens Syndrome: "Genetic imprinting- Differential modification of the expression of genes depending upon whether they are inherited from the mother or the father. This affects only certain segments of the human genetic complement,including PWS (Prader-willi Syndrome, see below) and Angelman syndrome on chromosome 15q." "Anglemens Syndrome- A rare syndrome reported in 1965 by Dr. H. Angelman and associated with a chromosome 15 deletion similar to that seen in PWS. In AS, however, the deletion is seen on the chromosome contributed by the mother, whereas those with PWS lack certain genes from the father. The clinical problems and appearance of AS and PWS are distinctly different. These two syndromes represent the first examples in humans of genetic imprinting." The above was copied (with modifications by me) from the following site: http://www.pwsausa.org/ Genetic imprinting is linked to AS. If the gene 15q11 is lost from the mothers side the disease is called Anglemens syndrome. If 15q11 is lost from the fathers side the disease is called Prader-willi Syndrome. So, in this case there is little to do with dominance or recessiveness. It mainly has to do with which parent the active or inactive gene comes from. For example: If a gene is passed through an egg it may always be inactivated, if a gene is passed through a sperm it may always be active - or vice versa. References and links are below. Enjoy! http://w ww.genetics.com.au/genetics/resource/factsht/9.html ht tp://www-personal.umd.umich.edu/~jcthomas/JCTHOMAS/1997%20Case% 20Studies/WA%20Hiltunen.html http://www.cerebralpalsy.or g/about-2.htm
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