The male-determining sex chromosome has lost 97 percent of its ancestral genes in the last 300 million years. If that rate ...

This video segment from NOVA: "Judgment Day: Intelligent Design on Trial" reveals how genetic evidence helped to confirm an important component of Darwin's theory of evolution by natural selection: ...

Each human cell contains 23 pairs of chromosomes that carry DNA within their nucleus. The X and Y chromosomes, commonly referred to as the sex chromosomes, are one such pair. They determine the ...

Men have lost most of the genes originally included on the Y chromosome during evolution, but those genes essential for survival have persevered, new research finds. Many of the remaining Y chromosome ...

Chromosomes are blocks of DNA (deoxyribonucleic acid). They contain very detailed and specific instructions that determine: How the cells in a baby's body develop. What features the baby will have, ...

Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from ...

Normally, an extra pair of chromosomes would be considered dangerous. But what if we could design our own? According to biologists, we could create custom-built chromosomes to fix a variety of health ...

Determining one’s own sex or that of another used to be a simple matter. First, there was the matter of appearance, whether a person looked like a male or looked like a female. If appearance produced ...

A team of scientists at the Sloan Kettering Institute has discovered how the X and Y chromosomes find one another, break, and recombine during meiosis even though they have little in common. As ...

A two-cell embryo of , stained to visualize DNA (red) and the cell membrane (green). One of the worst things that can happen to a cell is to end up with the wrong number of chromosomes. This can ...

New research shows that the male X chromosome is silenced in some types of cancer. Researchers evaluated how a certain gene affects the male X chromosome in cancer cells. Experts explain why these new ...

Triploidy is a condition that affects 1% to 3% of pregnancies. It’s when a developing baby has an extra set of chromosomes, the thread-like structures that carry DNA. A triploidy pregnancy usually ...