[Immunogenetic markers (BF, C2, C4, 21-OH, TNF alpha, TCR beta, Ig) and insulin-dependent diabetes in the Tunisian population: serological and molecular study].
48 Tunisian people suffering from the IDDM auto-immune disease were compared to 35 control healthy persons for the polymorphisms of the complement BF, C2 and C4 proteins and genes, of the IgG (Gm allotypes) as well as of the TNF alpha and TCR C beta genes. Our study shows that the BFF1-C4A3-C4BQO and BFS-C4AQ0-C4B1 complotypes are associated to IDDM (RR of 2.97 and 3.07 respectively), as previously reported for other circummediterranean populations. The frequency of the Gm 21.28; 1.17; .. haplotype is increased, but not significantly, among the patients. The RFLP analysis reveals that the 2.65 kb SacI allelic restriction fragment of the C2 gene may be considered as a genetic marker of susceptibility to IDDM because its frequency raises to 0.206 among the patients vs 0.021 in the healthy individuals (p less than 0.001). The frequencies of the C4AQ0 and C4BQ0 alleles are more important among the IDDM patients than within the control sample, but the only C4BQ0 allele frequency is significantly increased. Both C4AQ0 and C4BQO result mainly from deletions. The frequencies of the allelic restriction fragments of the TNF alpha and TCRC beta genes are not significantly different among the patients and the controls. But the small sample size don't allow us to conclude definitively. It would be very interesting to extend the RFLP analysis to the TCR V beta and V alpha gene regions on more numerous samples.
Ben Salem
M
M
Institut Pasteur, Tunis Belvédère, Tunisie.
Ghanem
N
N
Kneissi
T
T
Abbal
M
M
Dugoujon
J M
JM
Ben Chibani
J
J
Ellouze
F
F
Lefranc
G
G
D000293:Adolescent; D000328:Adult; D002648:Child; D003175:Complement C2 / Q000235:genetics; D003181:Complement C4 / Q000235:genetics; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology; D005260:Female; D005819:Genetic Markers; D006801:Humans; D007125:Immunogenetics; D007136:Immunoglobulins / Q000235:genetics; D008285:Major Histocompatibility Complex / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013255:Steroid 21-Hydroxylase / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics; D014416:Tunisia
D003175:Complement C2; D003181:Complement C4; D005819:Genetic Markers; D007136:Immunoglobulins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D014409:Tumor Necrosis Factor-alpha; D013255:Steroid 21-Hydroxylase
Marqueurs immuno-génétiques (BF, C2, C4, 21-OH, TNF alpha, TCR beta, Ig) et diabète insulino-dépendant dans une population tunisienne: études sérologique et moléculaire.