Sex determination at birth is decided on the chromosomes the baby has. A female has two X chromosomes, whereas a male has one X and one Y chromosome. According to Medline Plus, in every cell, humans ...

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

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 ...

Genes are segments of DNA (deoxyribonucleic acid) that are located inside every human cell. The DNA inside each cell is tightly coiled in structures called chromosomes. Each chromosome contains a ...

In what might be a surprise for some, the male sex chromosome is far more complex than its female counterpart. This is why it’s taken scientists so long to work out exactly what makes a male a male.

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, ...

Most people are born with 46 chromosomes that are divided into 23 pairs. Chromosome pairs carry genes from each parent, which determine a person’s physical characteristics, like their height or eye ...

Hermit crabs have the most chromosomes of any animal, with 254. Chromosomes carry genetic information in the form of DNA. Genes located on autosomes determine the inheritance of physical traits. Sex ...

Mosaic trisomy 8 is a rare genetic condition caused by an extra chromosome. Sometimes called trisomy 8 mosaicism, this condition develops well before birth. It's a result of an abnormality in how ...

Did you know that your baby’s genetic makeup was determined at conception? From the moment the sperm met the egg, your little one’s genetic code — DNA — began forming. It’s made up of 23 pairs of ...

It honors the 50th anniversary of the discovery that genes could cause cancer. Cancer researchers from around the country are in Philadelphia today feting the 50th anniversary of the discovery of the ...