Marfan syndrome in China: a collective review of 564 cases among 98 families.
This is a collective review of 564 patients with Marfan syndrome among 98 pedigrees reported from 18 provinces and cities in China over a 37-year period from 1951 to 1987. A positive family history of Marfan syndrome was found in 74.3% of the patients: the mode of inheritance was dominant in 73.8% and recessive in 0.5%. Sporadic cases occurred in 25.7%. A screening of 29,067 children found five children with Marfan syndrome, giving a prevalence of 17.2 per 100,000 of the population, a gene frequency of 8.61 per 100,000 genes, and a penetrance of 71.69%. Pleiotropy was clear in these cases: arachnodactyly in 77%, ectopia lentis in 86.8%, and dilated aortic root in 80.1%. Chromosome examination showed no regular aberrations except in a family of five in whom a giant-satellited chromosome 14 was found in three afflicted members but not in the two unaffected relatives. The high prevalence of aortic root dilation in Marfan syndrome makes echocardiography the most useful and practical means of diagnosis. Close follow-up and regular echocardiographic evaluation are indicated not only in patients with Marfan syndrome but also in their families, for both diagnostic and therapeutic purposes.