X-linked dominant inheritance: Difference between revisions

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'''X-linked dominant inheritance''', sometimes referred to as '''X-linked dominance''', is a mode of [[genetics|genetic inheritance]] by which a [[dominant gene]] is carried on the [[X chromosome]]. As an inheritance pattern, it is less common than the [[X-linked recessive inheritance|X-linked recessive]] type. In medicine, X-linked dominant inheritance indicates that a gene responsible for a [[genetic disorder]] is located on the X chromosome, and only one copy of the [[allele]] is sufficient to cause the disorder when inherited from a parent who has the disorder.

X-linked dominant traits do not necessarily affect males more than females (unlike [[X-linked recessive]] traits). The exact pattern of inheritance varies, depending on whether the father or the mother has the trait of interest. All daughtersfathers ofthat anare affected fatherby willan alsoX-linked bedominant affecteddisorder, butwill nonehave ofaffected hisdaughters, sonsbut will benot affected (unlesssons. However, if the mother is also affected). Inthen addition,sons thewill motherhave a chance of anbeing affected, sondepending on whether a dominant or recessive X chromosome is alsopassed affectedon. (butWhen notthe necessarilyson is affected the othermother waywill round)always be affected.

Some scholars have suggested discontinuing the terms dominant and recessive when referring to X-linked inheritance due to the multiple mechanisms that can result in the expression of X-linked traits in females, which include cell autonomous expression, skewed X-inactivation, clonal expansion, and somatic mosaicism.<ref>{{cite journal |doi=10.1002/ajmg.a.30123|pmid=15316978|title=Inheritance of most X-linked traits is not dominant or recessive, just X-linked|journal=American Journal of Medical Genetics|volume=129A|issue=2|pages=136|year=2004|last1=Dobyns|first1=William B.|last2=Filauro|first2=Allison|last3=Tomson|first3=Brett N.|last4=Chan|first4=April S.|last5=Ho|first5=Allen W.|last6=Ting|first6=Nicholas T.|last7=Oosterwijk|first7=Jan C.|last8=Ober|first8=Carole}}</ref>