Inheritance of most X-linked traits is not dominant or recessive, just X-linked

摘要: The existence of X-linked disorders in humans has been recognized for many centuries, based on lessons religious texts and observations specific human families (e.g., color blindness or Daltonism). Our modern concepts Mendelian (including X-linked) inheritance originated just after the turn last century. Early dominance recessiveness were first used conjunction with autosomal traits, then applied to "sex"-linked traits distinguish recessive dominant inheritance. former was defined as vertical transmission which carrier women pass disorder affected sons, while latter daughters males are always affected, transmitting offspring both sexes. However, such adrenoleukodystrophy, fragile X syndrome, ornithine transcarbamylase deficiency do not fit these rules. We reviewed literature 32 recorded information penetrance expressivity As expected, an index severity phenotype (defined our Methods) high males, low females. Contrary standard presentations inheritance, highly variable analysis classified 28% studied, intermediate 31%, 40%. proportion is difficult reconcile definitions They capture extraordinarily take into account multiple mechanisms that can result disease expression females, include cell autonomous expression, skewed X-inactivation, clonal expansion, somatic mosaicism. recommend use terms be discontinued, all simply described following "X-linked" (C) 2004 Wiley-Liss, Inc.