Replication of HLA class II locus association with susceptibility to podoconiosis in three Ethiopian ethnic groups.

Podoconiosis, a debilitating lymphoedema of the leg, results from barefoot exposure to volcanic clay soil in genetically susceptible individuals. A previous genome-wide association study (GWAS) conducted in the Wolaita ethnic group from Ethiopia showed association between single nucleotide polymorphisms (SNPs) in the HLA class II region and podoconiosis. We aimed to conduct a second GWAS in a new sample (N = 1892) collected from the Wolaita and two other Ethiopian populations, the Amhara and the Oromo, also affected by podoconiosis. Fourteen SNPs in the HLA class II region showed significant genome-wide association (P < 5.0 × 10-8) with podoconiosis. The lead SNP was rs9270911 (P = 5.51 × 10-10; OR 1.53; 95% CI 1.34-1.74), located near HLA-DRB1. Inclusion of data from the first GWAS (combined N = 2289) identified 47 SNPs in the class II HLA region that were significantly associated with podoconiosis (lead SNP also rs9270911 (P = 2.25 × 10-12). No new loci outside of the HLA class II region were identified in this more highly-powered second GWAS. Our findings confirm the HLA class II association with podoconiosis suggesting HLA-mediated abnormal induction and regulation of immune responses may have a direct role in its pathogenesis.

'Why should I worry, since I have healthy feet?' A qualitative study exploring barriers to use of footwear among rural community members in northern Ethiopia.

OBJECTIVE: To explore the influence of personal, cultural and socioeconomic factors related to footwear use and non-use in northern Ethiopia. DESIGN: A qualitative study was conducted using focus group discussions and in-depth individual interviews. Data were collected using semistructured interview guides. SETTING: The study was conducted in East and West Gojjam Zones, Amhara region, northwest Ethiopia. PARTICIPANTS: A total of 91 individuals from 4 target groups participated in individual and group interviews: (1) non-affected community leaders including Idir (a form of social insurance) leaders, school principals, kebele (the lowest administrative unit) officials, health professionals, teachers, merchants and religious leaders; (2) affected men and women; (3) non-affected men and women not in leadership positions; and (4) school children (both male and female). RESULTS: Participants perceived a range of health benefits from donning footwear, including protection against injury and cold. Various types of shoes are available within the community, and their use varied depending on the nature of activities and the season. Personal and socioeconomic barriers hindered the desire to consistently use footwear. Widely established barefoot traditions and beliefs that footwear is uncomfortable, heavy and may weaken the feet have made the regular use of footwear uncommon. Economic constraints were also mentioned as hindering ownership and use of footwear. Distance from places where shoes could be bought also contributed to limited access. Cultural influences promoting gender inequality resulted in women being least able to access shoes. CONCLUSIONS: We identified several individual, cultural and socioeconomic barriers that influence individuals' decisions about and use of footwear in rural northern Ethiopia. Promoting education on the health benefits of footwear, curbing podoconiosis-related misconceptions and integrating these with economic empowerment programmes, may all improve the use of footwear.