Altera????es gen??ticas em casais com antecedentes de aborto recorrente no primeiro trimestre da gesta????o

O abortamento ?? considerado um problema multifatorial, cujas principais causas envolvidas na sua etiologia s??o os fatores ambientais (como exposi????o a subst??ncias t??xicas), gen??ticos, anat??micos, end??crinos, imunol??gicos, trombof??licos e doen??as infecciosas (como toxoplasmose, rub??ola). No entanto, os fatores gen??ticos s??o atribu??dos principalmente aos abortamentos de primeiro trimestre da gesta????o. As altera????es cromoss??micas, o polimorfismo C677T, no gene da metilenotetrahidrofolato redutase (MTHFR677C>T); o polimorfismo G1691A, no gene do Fator V de Leiden (FVL1691G>A), e o polimorfismo G20210A, no gene da protrombina (PRT20210G>A), t??m sido associados a problemas obst??tricos, incluindo aborto recorrente. O objetivo deste trabalho foi investigar associa????o entre as muta????es relacionadas ?? trombofilia, presen??a de altera????es cromoss??micas e a ocorr??ncia de aborto espont??neo recorrente e avaliar poss??veis intera????es entre as referidas muta????es e as altera????es cromoss??micas. A casu??stica foi composta por 151 mulheres com hist??ria de aborto recorrente, 94 parceiros e 100 controles (mulheres sem hist??rico de aborto). A investiga????o das muta????es foi realizada pela t??cnica de Rea????o em Cadeia da Polimerase- Polimorfismo de Tamanho de Fragmento de Restri????o. As altera????es cromoss??micas foram investigadas pela cariotipagem com banda???G. A frequ??ncia das altera????es cromoss??micas foi de 7,3% nas mulheres com abortamento recorrente e 1% nos controles (p=0,022), e de 2,1% nos parceiros. No entanto, a frequ??ncia dos alelos MTHR677C>T (23% versus 22,5%), FVL1691G>A (1,5% versus 1% ) e PRT20210G>A (1,45% versus 0%) foi similar entre casos e controles, respectivamente. No grupo investigado, foi observada associa????o entre aborto recorrente e altera????es cromoss??micas, mas n??o foi encontrada associa????o com os polimorfismos g??nicos investigados.Abortion is considered a multifactorial problem, the most important causes involved in its etiology are, environmental factors ( as exposure to toxic chemicals), genetic, anatomic, endocrine, immunological, thrombophilic and infectious diseases (such as toxoplasmosis, rubella). However, genetic factors are mainly attributed to abortions of the first trimester of pregnancy. Chromosomal abnormalities, MTHFR 677C>T, factor V Leiden 1691G>A and prothrombin 20210G>A mutations have been associated with obstetric problems, including recurrent miscarriage. The objective of this research was to investigate associations between mutations in three genes commonly associated to thrombophilic events, chromosomal abnormalities and the occurrence of recurrent miscarriage. As well evaluate possible interactions between these mutations and chromosomal abnormalities. The sample was comprised of 151 women with history of recurrent miscarriages, 94 partners and 100 control (women with no history of abortion). The investigation of the mutations was performed by Polymerase Chain Reaction (PCR)/ Restriction Fragment Length Polymorphism (RFLP). Chromosomal aberrations were investigated by karyotyping with G-banda. The frequency of chromosomal abnormalities was 7.3% in women with recurrent miscarriage and 1% in controls (p = 0.022), and 2.1% in the partners. However, the frequency of allele MTHR677C> T (23% versus 22.5%), FVL1691G> A (1.5% vs. 1%) and PRT20210G> A (1.45% vs. 0%) was similar for cases and controls, respectively. In the investigated group was found association between recurrent miscarriage and chromosomal abnormalities, but no association was found with the genetic polymorphisms investigated