Chromosomes are tightly coiled structures in each of your cells that contain DNA, the code for all life. DNA is organized in segments on chromosomes called genes. Humans typically have 46 chromosomes ...

Human sex chromosomes originated from a pair of autosomes, the ordinary or non-sex chromosomes that contain the majority of our genome and come in identical pairs. That ancestral pair of autosomes ...

Sex chromosomes are chromosomes, or packages of DNA, that are found inside the nucleus of all of your cells. There are two different kinds: X and Y, which determine whether you’re biologically male ...

When a woman becomes pregnant, the outcome of that pregnancy depends on many things—including a crucial event that happened while she was still growing inside her own mother's womb. It depends on the ...

Chromosomes are thread-like structures comprising DNA that are present inside the nucleus of every cell in the body. Specific segments of DNA are called genes. Every chromosome contains many genes, ...

A study of mice might explain why. By Gina Kolata It’s been known for more than half a century that many men lose their Y chromosomes as they age. But no one knew if it really mattered. The loss of Y ...