The importance of advanced parental age in the origin of neurofibromatosis type 1.

Von Recklinghausen neurofibromatosis (NF1) is an autosomal dominant disorder with a prevalence about 1/3,000 (1/2,000-1/5,000 in various population-based studies). About 30-50% of cases are sporadic, resulting from a new mutation. NF1 is fully penetrant by mid-childhood, stigmata, and medical problems (neurological, dermatological, endocrine, ophthalmological, oncological) are highly variable. Advanced paternal age (APA) has been known to increase the risk of new germline mutations that contribute to the presence of a variety of genetic diseases in the human population. The trend in developed countries has been toward higher parental age due to various reasons. In a cross-sectional study, in two university hospital centers, data on parental age of 103 children (41 female) born between 1976 and 2005 with sporadic NF1 were analyzed. Parental age at birth was compared with the Czech general population matched to birth year. The mean NF1 sporadic case paternal age at birth was 32.0 years (95% CI 30.7-33.3 years) compared with 28.8 years (95% CI 28.6-29.1 years) in the general population (P < 0.001). The mean maternal age at birth was 27.4 years (95% CI 26.3-28.5 years) compared with 25.8 years (95% CI 25.5-26.0 years) in the general population (P < 0.05). The case-control difference in the father's age was higher than it was for the mother's age. Sporadic NF1 cases accounted for 35.6% of our entire NF1 cohort. We confirmed an association of advanced parental and particularly paternal age with the occurrence of sporadic NF1.