Raimondi E, Lenti C, Romagnoni M, Negri R, Gambini E, Musetti L, De Carli L
Dipartimento di Genetica e Microbiologia A. Buzzati Traverso, Università di Pavia, Italia.
Eur Neurol. 1990;30(1):32-7. doi: 10.1159/000116636.
A number of problems concerning both clinical and genetic or cytogenetic aspects of the fragile-X syndrome remain unsolved. In the present work, a large 5-generation fragile-X family has been clinically and cytogenetically investigated. The results of our study indicated that an unusually high proportion of affected males was present in the family examined; all fragile-X-positive males were profoundly retarded and showed the phenotype typically described for this syndrome; moreover, we observed a variability of penetrance within the pedigree and all fragile-X-positive females in the 4th and 5th generation had some degree of mental impairment. A multistep mutation model has been proposed in order to explain some of these findings.
关于脆性X综合征的临床、遗传或细胞遗传学方面的许多问题仍未解决。在本研究中，对一个大型的五代脆性X家族进行了临床和细胞遗传学研究。我们的研究结果表明，在所研究的家族中，受影响男性的比例异常高；所有脆性X阳性男性都有严重的智力迟钝，并表现出该综合征典型描述的表型；此外，我们在系谱中观察到外显率的变异性，第四代和第五代所有脆性X阳性女性都有一定程度的智力损害。为了解释其中一些发现，提出了一个多步骤突变模型。
