Characterization of a novel nonsense mutation in the interleukin-7 receptor alpha gene in a Korean patient with severe combined immunodeficiency.
Although it has been suggested that defective interleukin 7 receptor (IL-7R) signaling is one of the principal causes of severe combined immunodeficiency disease (SCID) in mice and humans, little is known about the molecular and clinical characteristics of human IL-7Ralpha mutations. We report a novel mutation of the IL-7Ralpha gene in a Korean SCID patient with a greatly diminished T-cell count but normal numbers of B-cells and natural killer (NK) cells. Using direct sequencing and restriction fragment length polymorphism analysis, we identified a C-->T nucleotide change at position 638. This change resulted in a nonsense mutation (R206stop) in this patient. Both parents were heterozygous for C/T at this site. The results of this study emphasize the importance of characterization of IL-7Ralpha mutations in SCID patients with diminished T-cell numbers but normal numbers of B-cells and NK cells.
Jo
Eun-Kyeong
EK
Department of Microbiology, College of Medicine, Chungnam National University, Daejeon, Korea.
Kook
Hoon
H
Uchiyama
Toru
T
Hakozaki
Ikuko
I
Kim
Young-Ok
YO
Song
Chang-Hwa
CH
Park
Jeong-kyu
JK
Kanegane
Hirokazu
H
Tsuchiya
Shigeru
S
Kumaki
Satoru
S
D000328:Adult; D018389:Codon, Nonsense; D005260:Female; D006801:Humans; D007223:Infant; D007723:Korea; D008297:Male; D020395:Receptors, Interleukin-7 / Q000235:genetics*; D016511:Severe Combined Immunodeficiency / Q000235:genetics* / Q000276:immunology
D018389:Codon, Nonsense; D020395:Receptors, Interleukin-7; C415350:interleukin-7 receptor, alpha chain