Identification of C7orf11 (TTDN1) gene mutations and genetic heterogeneity in nonphotosensitive trichothiodystrophy.
We have identified C7orf11, which localizes to the nucleus and is expressed in fetal hair follicles, as the first disease gene for nonphotosensitive trichothiodystrophy (TTD). C7orf11 maps to chromosome 7p14, and the disease locus has been designated "TTDN1" (TTD nonphotosensitive 1). Mutations were found in patients with Amish brittle-hair syndrome and in other nonphotosensititive TTD cases with mental retardation and decreased fertility but not in patients with Sabinas syndrome or Pollitt syndrome. Therefore, genetic heterogeneity in nonphotosensitive TTD is a feature similar to that observed in photosensitive TTD, which is caused by mutations in transcription factor II H (TFIIH) subunit genes. Comparative immunofluorescence analysis, however, suggests that C7orf11 does not influence TFIIH directly. Given the absence of cutaneous photosensitivity in the patients with C7orf11 mutations, together with the protein's nuclear localization, C7orf11 may be involved in transcription but not DNA repair.
Nakabayashi
Kazuhiko
K
Program in Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, ON, Canada.
Amann
Daniela
D
Ren
Yan
Y
Saarialho-Kere
Ulpu
U
Avidan
Nili
N
Gentles
Simone
S
MacDonald
Jeffrey R
JR
Puffenberger
Erik G
EG
Christiano
Angela M
AM
Martinez-Mir
Amalia
A
Salas-Alanis
Julio C
JC
Rizzo
Renata
R
Vamos
Esther
E
Raams
Anja
A
Les
Clifford
C
Seboun
Eric
E
Jaspers
Nicolaas G J
NG
Beckmann
Jacques S
JS
Jackson
Charles E
CE
Scherer
Stephen W
SW
D000595:Amino Acid Sequence; D001483:Base Sequence; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics; D004247:DNA / Q000235:genetics; D004252:DNA Mutational Analysis; D004476:Ectodermal Dysplasia / Q000235:genetics*; D005260:Female; D006197:Hair / Q000002:abnormalities*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D010375:Pedigree; D010787:Photosensitivity Disorders / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013577:Syndrome
D004247:DNA