X chromosome

American  

noun

Genetics.

1. a sex chromosome of humans and most mammals that determines femaleness when paired with another X chromosome and that occurs singly in males.

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X-chromosome British  

noun

1. the sex chromosome that occurs in pairs in the diploid cells of the females of many animals, including humans, and as one of a pair with the Y-chromosome in those of males Compare Y-chromosome

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X-chromosome Scientific  

/ ĕks′krō′mə-sōm′ /

1. The sex chromosome that in female mammals is paired with another X-chromosome and in males is paired with a Y-chromosome. Very few genes on the X-chromosome have counterparts on the Y-chromosome, and since males have only one X-chromosome, any gene present on it (even if the gene is recessive in females) is expressed in males. In females, one of the two X-chromosomes in each cell is deactivated.

2. See more at sex chromosome See note at sex

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Etymology

Origin of X chromosome

First recorded in 1910–15

Example Sentences

"In this study, we successfully assembled the first complete cattle X chromosome and four autosomes. However, assembling the remaining chromosomes to the same level of completeness remains an aim for future work," Dr. Low said.

From Science Daily

Having a pair of X chromosomes may shield females from harmful mutations and extend their lifespan.

From Science Daily

Researchers suspected that the mutation causing the condition was somewhere on the X chromosome, because females, which have two X chromosomes, are less affected.

From The Wall Street Journal

As it a gene only on the X chromosome in this case controlling the pigment production then one missing piece of DNA is enough to turn a cat fully ginger.

From BBC

The abnormal IP gene is located on the X chromosome.

From BBC