[Genetic analysis of Japanese patients with Fanconi anemia: novel findings].

Fanconi anemia (FA) is an inherited bone marrow failure syndrome characterized by multiple congenital abnormalities, progressive bone marrow failure, and a predisposition to malignancies, resulting from mutations in one of the 22 known FANC genes (from FANCA to FANCW). The proteins encoded by these genes participate in a deoxyribonucleic acid interstrand cross-link repair pathway, the so-called FA/BRCA pathway. The 22 FANC genes include hereditary breast and ovarian cancer susceptibility genes, such as BRCA1 or BRCA2. Patients with FA display a wide range of clinical phenotypes owing to the genetic heterogeneity of the disease; therefore, the molecular diagnosis is critical for the appropriate management of such patients. Recently, we successfully subtyped 97% of the 117 Japanese patients with FA and identified 215 mutant alleles through a comprehensive strategy. In this review, the characteristics of genetic subtyping and mutated FANC gene variants in Japanese patients with FA and the genotype-phenotype correlation in FA are summarized. In addition, the carrier frequency of pathogenic FANC genes and risk of cancer among the FANC gene mutation carriers in general Japanese population are discussed.