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F Fumeron

Publications and source records attributed to F Fumeron.

48 records · Page 3Linked to original sources

HLA and longevity.

One hundred fifty-five healthy nonagenarians, 45 men and 100 women, all French Caucasians, were phenotyped for alleles of the A, B, C, DR loci of the HLA complex. The observed HLA antigen frequencies were compared to those of a control series of 133 males and 179 females whose ages ranged from 10 to 50 years. When comparing the total young and elderly series, no significant differences were observed with respect to HLA antigen distribution or heterozygosity at any of the loci. When taking sex difference into account, however, an excess of the Cw1 antigen was found in the group of elderly females (p less than 0.001) and an excess of the Cw7 antigen in the group of elderly males (p less than 0.001). Of particular significance was the fact that Cw7 belonged in this instance to a phenotypic combination (and most probably to the corresponding haplotype) A1/Cw7/B8/DR3 which was found significantly increased in male nonagenarians (p less than 0.001). These results support the hypothesis that certain HLA haplotypes are associated with survival advantage.

Adolescent↗

Studies on an isolated West Indies population: I. Analysis of HLA genotypes.

The transmission of HLA genes was studied in an isolated population of French origin on the lesser Antilles islands in the West Indies. The study of 74 unrelated individuals, 44 of whom were genotyped, was carried out for the alleles of HLA loci: A, B, C and Bf (proactivator factor of properdin). As a result of the founder effect and the inbreeding process, the HLA haplotypes were noted to be less polymorphic than in a French continental population. Two haplotypes: A2, Cw5, B12, BfS and A3, C-, B14, BfF represent 24% of the observed haplotypes, and only 2% of the reference haplotypes in France. No significant excess or deficit of homozygotes was observed at the A and B loci.

Deafness↗

[Polymorphism of aldose reductase gene and susceptibility to retinopathy and nephropathy in Caucasians with type 1 diabetes].

Polymorphisms of the -106 mutation and z - 2 or z + 2 microsatellites (-2.1 kb) of the Aldose Reductase (AR) gene have been associated to microangiopathic complications of the diabetes mellitus. The study aimed to establish a relation between the occurrence and progression of the renal and retinal complications and these polymorphisms. The genotypes were realised in 3 populations: DESIR (n = 369), non-diabetic control subjects from the general French population: GENEDIAB (n = 494), type 1 diabetic patients who are suffering from proliferative retinopathy associated with a variable seriousness nephropathy (absent: n = 157; incipient: n = 104; established: n = 126; advanced: n = 107); SURGENE (n = 310), type 1 diabetic patients whom the renal status is prospectively assessed since 1989 in one single center Angers University Hospital. The genotype of the -106 polymorphism was determined using the Molecular Beacons. For the microsatellites analysis, we used an automatized method (GeneScan Abi Prism 3100). There was a strong linkage disequilibrium between the z - 2 allele and the T allele (chi 2 = 120; p = 0.001). The frequency of the C-106T is similar for the DESIR and GENEDIAB cohorts (chi 2 = 3.32; p = 0.19); the Hardy Weinberg law was verified in this group (chi 2 = 0.001, 0.9; p = 1.5 and 0.5 respectively). The law was not verified for the SURGENE cohort (chi 2 = 4.7; p = 0.03) where the frequency of the TT genotype was significantly more important compared to the DESIR population (chi 2 = 6.4; p = 0.01). The z, z - 2 and z + 2 alleles was more frequent compared with other alleles (n = 909, 830 and 349; 39, 38 and 15%). The frequency of the C-106T and microsatellites genotypes did not parallel the nephropathy staging in the GENEDIAB population (chi 2 = 10.9, 2.7, 2.4; p = NS respectively). In the SURGENE population, the survival without renal events did not differ according C-106T and z - 2 or z + 2 microsatellites genotypes (log-rank: 0.6, 3.9, 0.1; p = NS respectively). At the end of the follow-up, we found an effect of the -106 mutation and of the z - 2 microsatellite on the staging of the retinopathy (chi 2 tendency test = 4.61, 0.12; p = 0.031, 0.02; 6 d.f., respectively). The logistic regression multivariable analysis shows that the retinopathy during the final evaluation is independently explained by several factors: diabetes duration (p < 0.0001; OR 21.756; 95% CI: 7.024-67.389), presence of nephropathy (p < 0.0001; OR: 4.086; 95% CI: 2.094-7.973), and genotype TT (p = 0.011; OR: 0.38; 95% CI: 0.18-0.803). In contrast, age of diabetes onset (p = 0.112; OR: 1.556; 95% CI: 0.9-2.692), median HbA1c (p = 0.164; OR: 1.479; 95% CI: 0.85-2.576) and sex (p = 0.156; OR: 1.495; 95% CI: 0.856-2.612) have no independent effect. In conclusion, the association of these AR genetic variants seems absent about the renal risk and slight about the retinal risk associated to the type 1 diabetes mellitus.

Adult↗

[Polymorphism insertion/deletion of apolipoprotein B gene: effect on lipid levels in obese patients].

Apolipoprotein B (apoB) is the major proteic component of LDL, VLDL and chylomicrons. Numerous polymorphisms of the apolipoprotein B gene have been described. Particularly, a polymorphism of insertion/deletion located in the coding part of the signal peptide of apoB, associated with modifications of lipid concentrations and the risk of cardiovascular disease, has been reported in the general population. Since obesity is frequently associated with dyslipidemias, the aim of our study was to assess the effect of the insertion/deletion polymorphism of the apolipoprotein B gene on lipid levels in obese subjects. 234 unrelated caucasian obese subjects (74 men and 160 women, aged 39.3 +/- 10.5, BMI : 32.8 +/- 4.7) were recruited. The insertion/deletion polymorphism was determined by electrophoresis in polyacrylamide gels after PCR amplification. The relative frequencies of the Ins and Del alleles were 0.71 and 0.29 respectively. These frequencies were similar to those found in other Caucasian populations. In the whole population, individuals with the Del/Del genotype had significantly higher total-cholesterol to HDL-cholesterol ratios (p = 0.004), LDL-cholesterol to HDL-cholesterol ratios (p = 0.01) and TG-VLDL levels (p < 0.05). They also showed a tendency for higher triglyceride levels (p = 0.09) and lower HDL-cholesterol, apolipoprotein AI and LpAI levels. The allele deletion results in the absence of three amino acids (Leu-Ala-Leu) in the signal peptide of apo B. In the obese people, these structural changes may have some effect on lipid metabolism and cause variation in serum lipid concentrations.

Adult↗

[HLA tracers and Cushing's syndrome (author's transl)].

HLA-A and B phenotypes were determined in 38 patients with Cushing's syndrome (29 Cushing's diseases, 9 others etiologies) and compared with those of 591 normal subjects. No significant differences was found in the HLA antigens distribution in the two groups. However the series is too small to definitely support the hypothesis of a lack of correlation with HLA. Indeed, the increased prevalence of B8 antigen in Cushing's disease (28%) as compared to that in the control group (17%), although not statistically significant, emphasizes the need for further typing of HLA-DR, particularly RDw3 which is known to be linked to D8 through desequilibrium and associated with several autoimmune diseases.

Cushing Syndrome↗

Genetic approach of family obesity: study of HLA antigens in 10 families and 86 unrelated obese subjects.

HLA A and B typing was performed in 86 unrelated obese subjects and in 10 families including at least one parent and one obese sibling. The results in the series of unrelated subjects show no significant difference in antigen frequencies as compared to the control series. However in the 10 families studied, a group of 5 families is characterized by a high penetrance of obesity. In this group, inheritance of obesity seems to be transmitted through a dominant mode, and antigen B 18 appeared 4 times out of 5. The possible existence of a genetic form of obesity is considered in the discussion.

Female↗

[Influence of apolipoprotein E polymorphism in alcoholic cirrhosis].

OBJECTIVE: To assess whether the polymorphism of apolipo-protein E was associated with the development of alcoholic cirrhosis and could influence the severity of liver injury evaluated by the Child-Pugh score. METHOD: We investigated 75 alcoholic patients with a histological diagnosis of cirrhosis, with negative HBV, HCV serology and a control group of 54 subjects. Polymorphism of apolipoprotein E was performed using PCR. RESULTS: There was no difference for the allele frequency and the genotype in the cirrhotic group and the control group. Cirrhotic patients with allele epsilon 2 had higher concentration of albumin (P = 0.01) and a higher level of apolipoprotein AII (P < 0.05) than those with allele epsilon 3. They also had a higher concentration of apolipoprotein AI than cirrhotic patients with allele epsilon 3 and epsilon 4 (P = 0.01). There was a statistical difference between the three genotype groups for prothrombin time (P = 0.01). There was no statistical difference between the three genotype groups for Child-Pugh score. CONCLUSIONS: Polymorphism of apolipoprotein E was not associated with the development of alcoholic cirrhosis. However patients with allele epsilon 2 had better hepatocellular function.

Adult↗