Thake A, Todd J, Bundey S, Webb T
Arch Dis Child. 1985 Nov;60(11):1001-7. doi: 10.1136/adc.60.11.1001.
Clinical observations were made on a series of 156 boys with severe mental retardation, before cytogenetic results were known. The clinical features that helped to distinguish the 14 boys with the fragile X chromosome from those without were: head circumference over the 50th centile, postpubertal testicular volume over the 50th centile, and an IQ between 35 and 70. If the above clinical features were all present, then the chance of finding the fragile X chromosome was 1 in 3.6, whereas the chance of finding this abnormality in any boy with severe idiopathic mental retardation, regardless of his clinical features, was 1 in 9. Two boys with fragile X syndrome did not, however, possess any of the above clinical features. Moreover, some of the other retarded boys had clinical features of the syndrome, or an X linked pedigree, but lacked the chromosome abnormality.
在细胞遗传学结果知晓之前，对156名重度智力障碍男孩进行了临床观察。有助于将14名具有脆性X染色体的男孩与无此染色体的男孩区分开来的临床特征为：头围超过第50百分位数、青春期后睾丸体积超过第50百分位数以及智商在35至70之间。如果上述所有临床特征都存在，那么发现脆性X染色体的几率为3.6分之一，而在任何重度特发性智力障碍男孩中，无论其临床特征如何，发现这种异常的几率为9分之一。然而，有两名脆性X综合征男孩并不具备上述任何临床特征。此外，其他一些智力发育迟缓的男孩具有该综合征的临床特征或X连锁谱系，但缺乏染色体异常。
