GENETICS OF AUTISM

犹他州自闭症项目旨在通过研究自闭症儿童及其一级家庭成员的病因异质性和家族传播的可能表型表现来识别自闭症的遗传和非遗传亚群。 非特异性精神发育迟滞或诵读困难的先证者家庭的对照组也在研究中。 研究人员在自闭症儿童及其母亲中发现了高频率的MHC C4 B无效等位基因。 在完成分型的26名先证者中，有一半人有无效等位基因。 在30位被分型的母亲中，47%的人有无效等位基因。 这与正常对照组中发现的20%的比率相比。 在17名完成HLA分型的自闭症儿童中，47%的人表现出与对照组相比增加的相同的扩展单倍型。 免疫遗传功能的第三个领域集中在DR α 1等位基因的高变区。 大约有一半的自闭症儿童具有功能相同的特定等位基因。 研究人群中的其他免疫缺陷是血浆中伊加水平低，自闭症儿童中B细胞抗原D8-17的频率增加。 总之，迄今为止获得的结果强烈表明，免疫因素与自闭症的发展有关。认知研究表明，自闭症儿童的执行功能平均得分明显低于全面智商得分的预测。 该方案的其他研究包括通过磁共振成像扫描进行的大脑体积测量。 数字化数据已经收集，目前正在处理中。

The Utah Autism Program Project aims to identify genetic and non-genetic subgroups of autism by studying possible phenotypic manifestations of etiologic heterogeneity and familial transmission in autistic children and their first-degree family members. Control groups of families with probands affected with non-specific mental retardation or dyslexia are also under study. The investigators have found a high frequency of the MHC C4B null allele in children with autism and their mothers. For the twenty-six probands with completed typing, half have had the null allele. For the thirty mothers typed, 47% have the null allele. This compares with the rate of 20% found in normal controls. In seventeen autistic children with completed HLA typing, 47% have manifest the same extended haplotypes previously found to be increased when compared to controls. A third area of immune genetic function focuses on the hypervariable region of the DR(1 allele. Approximately half of the autistic children have specific alleles that are functionally identical. Other immunologic defects in the population studied have been low levels of IgA in plasma and an increased frequency of the B-cell antigen D8-17 in autistic children. Taken together, the results obtained to date strongly suggest that immune factors are associated with the development of autism. Cognitive studies have demonstrated that mean scores for executive function fall significantly below that predicted by full-scale IQ scores in children with autism. Other studies that are part of this protocol include volumetric measurements of the brain done by magnetic resonance imaging scans. Digitalized data have been collected and are now being processed.