Tokyo, Japan – Researchers from Tokyo Metropolitan University have taken a big step in solving the mystery around why animals evolve sex chromosomes. It had long been proposed that sex chromosomes ...

The evolution of sex chromosomes influences reproductive biology and genome evolution across species. In Drosophila pseudoobscura, the Y chromosome has a distinct origin compared to Drosophila ...

A nearly gapless genome sequence of the echidna, an egg-laying mammal with multiple sex chromosomes, helps researchers to track genomic reorganization events that gave rise to a highly unusual sex ...

Sex is determined in a variety of different ways throughout the animal kingdom. In mammals, it is determined genetically, not by temperature, as it can be in reptiles. Typically, females have two X ...

Scientists have confirmed that the Atlas blue butterfly carries the most chromosomes of any animal, with 229 pairs. Unlike duplication, its chromosomes split apart, reshaping its genome in surprising ...

The 23 rd chromosome base pair contains what are known as our sex chromosomes. For most females, this pair contains two X chromosomes, while for most males, it contains one X chromosome and one Y ...

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 ...

Human biological sex is determined by the sex chromosomes X and Y. In most cases, females possess two X chromosomes, while males have one X and one Y. However, there is some evidence that the Y ...

In about one out of every 800 people, two chromosomes fuse together to form an unusual bond. These are known as Robertsonian chromosomes. It's a mystery that has long stumped scientists. Now, ...