Down Syndrome Discovery Has Implications for Human Genetic Engineering

The 21st human chromosome is the smallest of all our chromosomes. It contains only a few hundred genes and is only 1% of our total DNA. As most people know, an extra chromosome 21 causes Down Syndrome. What most people did not know until research published this week, is that tiny chromosome has an effect across the whole human genome.Instead of simply being an extra copy of each of the genes on chromosome 21, trisomy 21 has an effect on the expression of genes on other chromosomes. The Scientist has the story of the fascinating research that lead to this discovery:The deleterious effects of trisomy 21—the extra chromosome behind Down’s syndrome—can be seen across the entire genome, according to a study published today (April 16) in Nature. While studying a pair of monozygotic twins in which only one person had Down’s syndrome, a team led by Stylianos Antonarakis of the University of Geneva Medical School in Switzerland discovered that trisomy 21 can affect other chromosomes.This rare twin pair allowed the researchers to compare the effects of Down’s syndrome on gene expression in two otherwise genetically identical individuals. The researchers found that in the twin with Down’s syndrome, genes in territories along the chromosomes that are highly expressed in people without the disorder showed reduced expression, while genes in territories that are normally suppressed were more highly expressed.“The fact that they’ve got these really nice domain structures genome-wide ...
Source: Mary Meets Dolly - Category: Geneticists and Genetics Commentators Tags: Genetic Engineering Source Type: blogs