Chronic Periodontitis Genome-wide Association Study in the Hispanic Community Health Study / Study of Latinos

Area of Science:

• Genetics
• Periodontology
• Genomics

Background:

• Chronic periodontitis (CP) is a severe infectious disease with a known genetic component.
• Genome-wide association studies (GWASs) have identified several loci associated with CP.
• Previous GWASs have not focused on large, community-based Hispanic/Latino samples.

Purpose of the Study:

• To conduct the first GWAS of CP in a large, community-based Hispanic/Latino sample.
• To identify novel genetic loci associated with mean interproximal clinical attachment level, a quantitative trait of CP.
• To investigate the replication of identified loci in independent European-American and African-American cohorts.

Main Methods:

• A GWAS was performed on 10,935 Hispanic/Latino adults from the Hispanic Community Health Study / Study of Latinos.
• Genotyping and imputation were conducted using a custom array and the 1000 Genomes Project reference panel.
• Linear mixed models were used for association analyses, adjusting for covariates and population structure.

Main Results:

• A genome-wide significant association signal was identified in the 1q42.2 locus (TSNAX-DISC1 noncoding RNA, rs149133391).
• Four additional loci showed suggestive evidence of association (P < 5 × 10^-6).
• The TSNAX-DISC1 locus replicated in an African-American sample, and the 1q22 locus showed nominal significance.

Conclusions:

• This GWAS identified a novel genome-wide significant locus (TSNAX-DISC1) associated with CP in Hispanic/Latinos.
• The locus was independently replicated in an African-American population, suggesting a shared genetic component.
• The findings provide a genetic marker for future research into the mechanisms of CP.