New research shows the X chromosome influences disease risk, immunity and drug response beyond its role in sex.

Extra X chromosomes significantly increase the risk for systemic lupus erythematosus (SLE) and Sjögren disease, with the prevalence of these conditions being higher among patients with Klinefelter and ...

X-linked agammaglobulinemia (XLA) is an immune disorder that causes extremely low levels of B cells, which are an important part of the immune system. XLA can put a person at risk of frequent ...

X-linked hypophosphataemia (XLH) is the most prevalent heritable form of rickets in children and of osteomalacia in adults.

Mutations in FMR1, the gene encoding fragile X messenger ribonucleoprotein 1 (FMRP), located at Xq27.3 and discovered in 1991, are the leading single-gene causes of autism and intellectual disability.

In female mammals, one of the two X chromosomes is usually inactive and forms the so-called Barr body. The image shows a cell nucleus with the Barr body marked in green. Unlike men, who carry one X ...

Researchers have conducted what they say is the largest and most diverse study to date on how recessive genetic changes contribute to developmental disorders. The team, headed by researchers at the ...