Identification of nonsynonymous polymorphisms in the superantigen-coding region of IDDMK1,2 22 and a pilot study on the association between IDDMK1,2 22 and type 1 diabetes.
To investigate the possible involvement of IDDMK1,2 22/HERV-K18 in childhood type I diabetes mellitus, we identified two nonsynonymous A/G polymorphisms in the superantigen-coding region of IDDMK1,2 22 at the 290- and 461-nucleotide (nt) positions from the initial methionine codon and compared their frequencies in 74 Japanese patients with type 1 diabetes and in 54 nondiabetic controls. Although the G substitution was observed more frequently at either site in the patients than it was in the controls (7% vs. 4% at 290 nt, and 29% vs. 20% at 461 nt), the differences were not statistically significant. A weak significance of difference in the frequency of 461G was obtained only in an early-onset group of patients manifesting the disease at 5 years of age or less (n = 24) when compared with controls (38% vs. 20%; P = 0.03). However, in addition to the common absence of a particular allele among the expected four alleles, remarkable differences in allele frequencies were present between Japanese and European populations. This first trial investigating the association of IDDMK1,12 22 with type 1 diabetes presents intriguing suggestions for the role of this region in the etiology of autoimmune and infectious diseases.
Kinjo
Y
Y
Department of Molecular Biology, Ryukyu University School of Medicine, Nishihara, Okinawa, Japan.
Matsuura
N
N
Yokota
Y
Y
Ohtsu
S
S
Nomoto
K
K
Komiya
I
I
Sugimoto
J
J
Jinno
Y
Y
Takasu
N
N
D017668:Age of Onset; D000483:Alleles; D016022:Case-Control Studies; D002675:Child, Preschool; D003001:Cloning, Molecular; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology*; D005787:Gene Frequency; D006801:Humans; D007564:Japan; D008565:Membrane Proteins; D020641:Polymorphism, Single Nucleotide; D018089:Superantigens / Q000235:genetics*
C107453:ERVK-18 protein, human; D008565:Membrane Proteins; D018089:Superantigens