Human cells typically have 23 pairs of chromosomes; extra chromosomes are an anomaly known as aneuploidy. “If you look at normal skin or normal lung tissue, for example, 99.9% of the cells will have ...

Sometimes, the translocation happens later, after conception. There will be two populations of cells, one with normal chromosomes and one with the translocation. This is known as mosaicism.

An egg that has an extra set of chromosomes is fertilized by a normal sperm. Experts haven’t found any specific risk factors. Triploidy doesn’t run in families. It’s not linked to a mother ...

The apparently normal carriers of the translocation chromosome have had a somatic chromosome number of 45. The purpose of the present communication is to report 2 more families in which mongolism ...

Women, after all, manage just fine without one. What’s more, the Y chromosome has degenerated rapidly, leaving females with two perfectly normal X chromosomes, but males with an X and a ...

Their study, published online January 12, 2014 in Nature, used stem cells to correct a defective “ring chromosome” with a normal chromosome. Such therapy has the promise to correct chromosome ...

Now, Asato Kuroiwa at Hokkaido University in Japan and her colleagues have shown that one of the rat’s normal chromosomes has effectively evolved into a new male sex chromosome. The Y ...