Sequenced for the First Time: the Genome of Human Sperm
Human Sperm Cells Wikimedia Commons Scientists have sequenced the full genomes of 91 sperm from one man, the first complete sequencing of a human gamete cell. It demonstrates the vast genetic variation in one person, according to genetic researchers at Stanford. The 40-year-old sperm donor has healthy kids and his semen sample was normal, and researchers had already sequenced his whole genome using other cells. They were able to compare that result with the 91 individual sperm cells they isolated from his sample. This allowed an interesting view of recombination - the genetic mixing that ensures a baby's DNA contains genetic material from all four of its grandparents. Recombination causes genetic variation in babies because of how it mixes the parents' DNA. Human cells have 46 chromosomes - two copies of 23 chromosomes - and in reproductive cells, these are partitioned into one copy of each 23. When these gametes (sperm...