Parsian A, Todd R D
Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Am J Med Genet. 1997 Sep 19;74(5):475-9. doi: 10.1002/(sici)1096-8628(19970919)74:5<475::aid-ajmg3>3.0.co;2-n.
There have been several conflicting reports of association of monoamine oxidase (MAO) A gene polymorphisms and bipolar affective disorder. In order to determine the possible role of the MAO region in susceptibility to affective disorders in an independent sample, we have genotyped 83 probands of bipolar affective disorder families, 56 sets of parents of bipolar probands, and 84 normal controls for intronic simple sequence repeat polymorphisms of the MAO-A and MAO-B genes. For MAO-A there were no significant differences in allele frequencies between bipolar and normal control groups for both genders. However, for MAO-B there were significant differences between groups for both genders. In contrast, allele-wise haplotype relative risk analysis for the 56 bipolar proband-parent trios found no significant differences between transmitted and non-transmitted allele frequencies for MAO-A or B. These data do not support the association of MAO-A or B with bipolar affective disorder but do demonstrate that undetected population stratification can be an important source of bias in case-control studies.
关于单胺氧化酶（MAO）A基因多态性与双相情感障碍之间的关联，已有数篇相互矛盾的报道。为了在一个独立样本中确定MAO区域在情感障碍易感性中可能发挥的作用，我们对83例双相情感障碍家族的先证者、56对双相先证者的父母以及84名正常对照者进行了MAO - A和MAO - B基因内含子简单序列重复多态性的基因分型。对于MAO - A，双相情感障碍组与正常对照组之间，无论男女，等位基因频率均无显著差异。然而，对于MAO - B，无论男女，两组之间均存在显著差异。相比之下，对56个双相先证者 - 父母三联体进行的逐等位基因单倍型相对风险分析发现，MAO - A或B的传递等位基因频率与未传递等位基因频率之间无显著差异。这些数据不支持MAO - A或B与双相情感障碍之间的关联，但确实表明未检测到的群体分层可能是病例对照研究中偏差的一个重要来源。
