RMRP mutations in Japanese patients with cartilage-hair hypoplasia.
We examined 12 Japanese patients with metaphyseal chondrodysplasia (MCD) for mutations in the ribonuclease mitochondrial RNA processing gene (RMRP), and identified four novel mutations in two patients with typical and atypical cartilage-hair hypoplasia (CHH), a form of MCD characterized by extra-skeletal manifestations including hypoplastic hair and defective immunity. A patient with typical CHH had a 17-bp duplication at +3 and a de novo 182G > A. The other patient with atypical CHH had a 17-bp insertion at -20 and a 218A > G. Expression analysis revealed that the allele with this insertion mutation in the promoter region silenced the gene. Spectrum analysis of the mutations and polymorphisms in RMRP showed marked difference between the Japanese and other ethnic groups. Such ethnic and phenotypic difference should be taken into account in mutation analysis of the gene.
Nakashima
Eiji
E
Laboratory for Bone and Joint Diseases, SNP Research Center, RIKEN, Tokyo, Japan.
Mabuchi
Akihiko
A
Kashimada
Kenichi
K
Onishi
Toshikazu
T
Zhang
Junwei
J
Ohashi
Hirofumi
H
Nishimura
Gen
G
Ikegawa
Shiro
S
D000293:Adolescent; D001483:Base Sequence; D002648:Child; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004252:DNA Mutational Analysis; D004722:Endoribonucleases / Q000235:genetics*; D005260:Female; D006801:Humans; D007564:Japan; D009154:Mutation; D010009:Osteochondrodysplasias / Q000235:genetics* / Q000473:pathology; D011401:Promoter Regions, Genetic / Q000235:genetics
D004247:DNA; D004722:Endoribonucleases; C058330:mitochondrial RNA-processing endoribonuclease