Hereditary Red Cell Membrane Disorders in Japan: Their Genotypic and Phenotypic Features in 1014 Cases Studied

This study describes the characteristic features of the incidence of hereditary red cell membrane disorders in the Japanese population based on studies of 1014 cases of these disorders from 605 kindred.Among them, there were 581 cases of hereditary spherocytosis (HS) from 303 kindred, 137 cases of hereditary elliptocytosis (HE) from 68 kindred, 104 cases of hereditary stomatocytosis (HSt) from 64 kindred, and 34 cases of protein 4.2 (P4.2) anomalies from 20 kindred, and 41 cases of membrane lipid anomalies from 27 kindred.In HS patients, eleven mutations of the band 3 (B3) gene, 15 mutations of the ankyrin gene, and three mutations of the protein 4.2 (P4.2) gene, which are pathognomonic for this disorder, were identified. Most of these mutations had not been reported and, with few exceptions, were specific to the Japanese population. P4.2 abnormalities also appear to be unique to the Japanese population. The biochemical and biophysical functions of P4.2 are associated with stabilization of the cytoskeleta...