Marked differences of haplotype tagging SNP distribution, linkage, and haplotype profile of IL23 receptor gene in Roma and Hungarian population samples

Representing vulnerable populations in genetic studies: The case of the Roma

Moreau () has raised concerns about the use of DNA data obtained from vulnerable populations, such as the Uighurs in China. We discuss another case, situated in Europe and with a research history dating back 100 years: genetic investigations of Roma. In our article, we focus on problems surrounding representativity in these studies. We claim that many of the circa 440 publications in our sample neglect the methodological and conceptual challenges of representativity. Moreover, authors do not account for problematic misrepresentations of Roma resulting from the conceptual frameworks and sampling schemes they use. We question the representation of Roma as a "genetic isolate" and the underlying rationales, with a strong focus on sampling strategies. We discuss our results against the optimistic prognosis that the "new genetics" could help to overcome essentialist understandings of groups.

Characteristics of inflammatory bowel disease in patients of Roma/Gypsy ethnicity. A case-control study

BACKGROUND

Peculiarities of inflammatory bowel disease (IBD) have been explored in ethnic groups, such as Asians, Hispanics, and Afro-Americans, but not in other ethnic minorities, such as Roma/Gypsies.

METHODS

In a retrospective, hospital-based study, all adult Roma/Gypsy patients included in the IBD databases of seven Spanish centres were identified as cases. For each Roma/Gypsy patient, a Caucasian patient, matched for several demographic features, was searched as a control. Data on phenotypic features, therapeutic requirements, and familial aggregation were recorded.

RESULTS

Sixty-eight Roma/Gypsy patients were identified, 29 of them being women. The mean age at diagnosis of IBD was 24.9±9.5years, and the mean time elapsed since diagnosis was 96.6±72.2months. Roma/Gypsy IBD patients showed a significantly higher rate of familial aggregation (43%) than their Caucasian controls (9%) (p=0.00001). CD in Roma/Gypsies had more often a complicated pattern (mainly penetrating) while UC patients showed a marked trend to more often developing extraintestinal manifestations. In addition, Roma/Gypsy IBD patients had a somewhat greater need for immunosuppressants, biological agents or surgery.

CONCLUSIONS

These are the first data on IBD in Roma/Gypsy patients. Familial aggregation is the most prominent feature in these patients, suggesting a predominant role of genetics in its pathogenesis.

Distinct Penetrance of Obesity-Associated Susceptibility Alleles in the Hungarian General and Roma Populations

AIMS

The aim of our study was to explore differences in genetic predisposition to obesity between the Hungarian general and Roma populations.

METHODS

A total of 1,152 samples from the Hungarian Roma population and 1,743 samples from the Hungarian general population were genotyped for 20 single nucleotide polymorphisms (SNPs) associated with the risk of obesity. Two types of multilocus genetic risk scores were constructed to estimate the combined effect of selected SNPs.

RESULTS

Risk allele frequencies differed significantly between the two populations for 11 SNPs, with no enrichment in any of the two study groups. Variants (rs1558902, rs1121980, rs9939609, and rs9941349) in the fat mass and obesity-associated (FTO) gene exhibited strong but ethnicity-independent association with obesity. Genetic risk scores showed stronger associations with obesity in the Roma population compared with the Hungarian general population; however, without significant gene-population interaction.

CONCLUSION

Differences in obesity prevalence between the Hungarian general and Hungarian Roma populations could not be explained by their distinct genetic susceptibility, rather by ethnicity-related environmental and behavioral factors. Nonetheless, particular gene-environment interactions might contribute to the distinct penetrance of the obesity-associated genetic factors in populations of different ethnic backgrounds.