TSLP gene gene variants linked to asthma
MedWire News: Two single nucleotide polymorphisms (SNPs) in the thymic stromal lymphopoietin gene (TSLP) are associated with a gender-specific reduced risk for asthma, study results show.
"TSLP appears to be a key regulator of allergic asthma in mouse models [and], in humans, there are increased numbers of TSLP mRNA+ bronchial epithelial cells in asthmatics versus controls," explain Juan Celedón (Channing Laboratory, Boston, Massachusetts, USA) and colleagues.
However, they add that "multiple lines of evidence suggest that sex might modify the role TSLP plays in asthma."
To investigate further, the team studied DNA samples collected from 417 Costa Rican children with asthma and their families.
Significant associations were then validated in genetic data collected from 470 White and African-American asthmatic participants in the Childhood Asthma Management Program, 2772 White and Hispanic participants (1206 asthmatics) in the Children's Health Study, 935 African-Americans (464 asthmatics) in the Genomic Research on Asthma in the African Diaspora study, and 7477 White participants (961 asthmatics) in the Framingham Heart Study.
Using pooled data from all cohorts, the researchers found that two SNPs (rs1837253 and rs2289276) in TSLP were significantly associated with a reduced risk for asthma.
Further analysis by gender revealed that the T allele of rs1837253 was significantly associated with a reduced risk (up to 16%) for asthma in males only, while the T allele of rs2289276 was significantly associated with a reduced risk (up to 13%) for the condition in females only.
Celedón and team conclude in the journal Allergy: "We have identified a sex-specific association between two polymorphisms in the genomic region of TSLP and asthma.
They add: "Our work provides support to the growing body of evidence that TSLP plays an important role in the pathogenesis of asthma. In addition, our findings provide one genetic clue to the long-standing, but puzzling, relation between sex and asthma."
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By Mark Cowen