Neurofibromatosis type 1 (NF1; OMIM 162200) is an autosomal dominant disorder caused by a wide variety of germline mutations in the NF1 gene. Nearly all individuals with NF1 exhibit café-au-lait macules before the age of 2,¹ but can also develop numerous other medical problems, including autism, cognitive deficits, tumors, and congenital heart defects. Although the clinical variability inherent in NF1 has been attributed to stochastic events, it is possible that the specific germline NF1 mutation might be one factor underlying this heterogeneity. To illustrate this point, we report a family with 2 affected members harboring a missense mutation in the NF1 gene who lack the classic features of NF1.

1 型神经纤维瘤病（NF1；OMIM 162200）是一种常染色体显性遗传疾病，由NF1基因中的多种种系突变引起。^{几乎所有患有 NF1 的人都会在 2 岁、 1}岁之前出现牛奶咖啡斑，但也可能出现许多其他医学问题，包括自闭症、认知缺陷、肿瘤和先天性心脏缺陷。尽管 NF1 固有的临床变异性归因于随机事件，但特定的种系NF1突变可能是导致这种异质性的一个因素。为了说明这一点，我们报告了一个家庭，其中有 2 个受影响的成员在NF1基因中存在错义突变，他们缺乏 NF1 的经典特征。