Re: what are some of the most bizarre chromosomal abnormalities?

Some of the most bizarre chromosomal abnormalities are based on too many chromosomes. Each person should have 46 chromosomes (23 pairs) one set from each parent. However, sometimes people have 47 chromosomes because one set has three chromosomes instead of two. This is known as trisomy. Some examples of trisomy are as follows: Trisomy 21 (three of chromosome 21) results in Down syndrome. Babies born with Down syndrome usually survive into adulthood. Other chromosomal abnormalities are trisomy 13, Patau's syndrome, and trisomy 18, Edward's syndrome. Both are relatively rare but serious conditions that cause severe mental retardation and physical deformities. Babies born with either of these trisomies usually do not survive beyond their first year. There are probably other abnormalities that are related to errors in the gene code in the chromosomes but these three are "bizarre" (Downs however is not uncommon) Michael Watson Information can be found using gale encyclopedia and the following link about sex chromosome abnormalities http://www.stanford.edu/group/cap/research/syndromes_disorders/sca/