Herencia no tradicional, no mendeliana

Abstract

Qbjedvc: ilustrar como las modalidades no tradicio"ales de he'encia humana, que incluyen el mosaicismo gonacal. la herencia rrrccondrial, la impror.ta {imprinting) genomica.. la disomia jnioareital y mutaciones tnestables o repetition de trinucleolidos, permiten explicar los trasrornos que sufre un numero 'mporta n te de pacientes con areccio-nes neurocgcas de origen genetico. Metodo: se revisaron retrospectivcrrente los registros clinicos de todos los pa-cientes que consultaron en una unidad de referenda entre julio de 1992 y julio de 1995. Resultados: entre 753 con-suites regisrradas, 339 ;4.5%] eran primeras consultas. En 33 de es'as [ 1 C%) la hipotesis era un problema de herencia no iradicicnal. sindromes de X-fragil (amplificacion ae tnpletes o mutaciones ineslablesj, Proder-Willi y Angelman iimprontc genom ca y discmia unipcrervali y atrofia optica de Leber [herercio mitocond'io!). Se incluye tambien el ana isis de ir pacienle con srdrome de Apert cuyo case pernile proponer al rnosaicismo gonadal ccmo otro meccnismo de estos tipos de herencia. Concliisior.es: el rrodelo mendeliano de herencia ofrece el marco de referenda pare la Ttayoria de las afecciones genet'cas en el hombre. Sin embargo "ay famil'cs cuyos antecedentes no calzan en ese esquema, pero si en los de herencia no tradic'onct. Pa la bras clave: enfermedades hereditarias.. herencia, no tradicional, no menceliana.i Non traditional mechanisms of inheritance in human diseases Ob/ecf/ve; to illustrate non t'adiciona ncn mendelian mechanisms responsible of inheritance in several human diseases Patients and methods', the clinical records of all patients submited f c a unive'sity associated outpatient genetic clinic by SLpposedely hereditary neuro'og^cal ciseases from July 1992 throughout july 1995 were retrospectively revewec. Results, during this period 339 (45%) first appointments and 414 (55%) fol cw up v ; sits were recorded. Among first "ine parierts, a disease "nherited oy a non tradic'oral non mendelian mechanism was suspected in 33 (10%). Definite a'ccnosis were, in "hose cases, Prader Willi and Ange'rrian syndromes (genomic imprinting and unipcrental disomyl, fragile X (triplet nucleotide repeals and jnstabe mu^rions), Leber's optic atrophy [rn'tochcndria inheii'ance! and Apert syndrome. This late was included because "I allows to propose gcncdal mosaicism as another fo'rn of -on tradicionol inhe-'tance. Conclusion the tracitional mendelicn model of inhe r 'tance, based on chromosomai segregation, provides the framework -or -nost of our thinking about hjmar-genetics disorders, however there ere clirical situations "hat oc not fit quite easily into this screme. Noi Iradicional mechanisms of : nheritance allo\v to exp ain and iden'ify nany of these cases.