Genetics and Family Health

The Human Genome Project marked a new beginning toward understanding the genetic basis of an increasing number of medical conditions. In addition to many gene-disease associations that were unveiled and characterized, significant attention was captured by the 0.1% of the genome that represents interindividual variability. Over 3 million interindividual differences at the nucleotide level, known as single nucleotide polymorphisms, were catalogued, and many of them shape predispositions to medical conditions, adverse reactions in response to therapeutic agents, or sensitivity to environmental chemicals. More recently, an additional source of interindividual genetic variability—the deletion or duplication in varying numbers of genes or chromosomal regions as large as 3 million bases—became known as copy number variation (CNV). CNVs were linked to medical conditions such as autism spectrum disorders, ...