Humans normally have 46 chromosomes in each cell, divided into 23 pairs. Two copies of chromosome 8, one copy inherited from each parent, form one of the pairs. Chromosome 8 spans about 146 million DNA building blocks (base pairs) and represents between 4.5 percent and 5 percent of the total DNA in cells.
Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. Chromosome 8 likely contains between 700 and 1,100 genes.
Genes on chromosome 8 are among the estimated 20,000 to 25,000 total genes in the human genome.
Researchers at Harvard-affiliated Dana-Farber Cancer Institute have pinpointed a crucial gene on which the normal development of the body's entire blood system depends. If the gene is absent, even the most basic blood stem cells cannot be generated. In a mutated form, this gene can cause a rare and devastating form of leukemia.
International research teams studying two distinct populations have found variants in a gene that may predispose people to type 2 diabetes, the most common form of the disease. The researchers, who collaborated extensively in their work, report their findings in companion articles in the April issue of Diabetes.