Jorde L B, Hasstedt S J, Ritvo E R, Mason-Brothers A, Freeman B J, Pingree C, McMahon W M, Petersen B, Jenson W R, Mo A
Department of Human Genetics, University of Utah School of Medicine, Salt Lake City 84112.
Am J Hum Genet. 1991 Nov;49(5):932-8.
A complex segregation analysis of autism in 185 Utah families was carried out using the mixed model. The 209 affected individuals in these families represent nearly complete ascertainment of the autistic cases born in Utah between 1965 and 1984. The sibling recurrence risk for autism was 4.5% (95% confidence limits 2.8%-6.2%). Likelihoods were maximized for major-gene models, a polygenic model, a sibling-effect model, and a mixed model consisting of major-gene and shared-sibling effects. The analysis provided no evidence for major-locus inheritance of autism. Subdivision of the sample according to the probands' IQ levels showed that sibling recurrence risk did not vary consistently with IQ level. A segregation analysis of families in which the proband had an IQ less than 50 also failed to provide evidence for a major locus. However, because of the etiologic heterogeneity of this disorder, genetic analysis of other meaningful subsets of families could prove informative.
利用混合模型对185个犹他州家庭的自闭症进行了复杂的分离分析。这些家庭中的209名受影响个体几乎涵盖了1965年至1984年间在犹他州出生的自闭症病例。自闭症的同胞复发风险为4.5%(95%置信区间2.8%-6.2%)。对于主基因模型、多基因模型、同胞效应模型以及由主基因和共享同胞效应组成的混合模型,似然性达到了最大值。该分析没有提供自闭症主基因遗传的证据。根据先证者的智商水平对样本进行细分后发现,同胞复发风险并未随智商水平一致变化。对先证者智商低于50的家庭进行的分离分析也未能提供主基因座的证据。然而,由于这种疾病的病因异质性,对其他有意义的家庭亚组进行基因分析可能会提供有用信息。