Humans normally have 46 chromosomes in each cell, divided into 23 pairs. Two copies of chromosome 9, one copy inherited from each parent, form one of the pairs. Chromosome 9 is made up of about 140 million DNA building blocks (base pairs) and represents approximately 4.5 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 9 likely contains between 800 and 1,300 genes.
Genes on chromosome 9 are among the estimated 20,000 to 25,000 total genes in the human genome.
Researchers at UF Scripps Biomedical Research have created a potential treatment for a major factor in the development of ALS and dementia that functions by removing disease-causing RNA segments.
The wild ancestor of maize, teosinte, contains three times as much seed protein as the majority of cultivars of maize today. The mechanisms causing the declining seed protein content in maize hybrids and inbred lines were identified by researchers at the Chinese Academy of Sciences Headquarters.
According to a new study, patients with head and neck cancer who have more chromosome 9 genetic material in their cancer cells survive three times longer after accepting immunotherapy than patients who have less of it.