Association between brain-derived neurothropic factor variants and asthma in Chinese Han children

To identify the markers contributing to genetic susceptibility to asthma in Chinese Han children.

This study examined the potential association between childhood asthma and seven single nucleotide polymorphisms of Brain-derived Neurotrophic Factor (BDNF) - SNPs, rs16917204, rs6265, rs7103873, rs16917237, rs56164415, rs13306221 and rs10767664 - using the MassARRAY system. The participants, recruited between May 2009 and July 2012, were 319 children with asthma (mean age 9.82 ± 1.57 years) recruited from a hospital paediatric department and 309 healthy controls (mean age 10.25 ± 1.36 years), recruited from the medical examination centre at the same hospital.

We observed a significant association for rs6265 (χ(2)  = 9.851, p = 0.002, OR = 1.427, 95% CI = 1.143-1.783), located in exon 4 of the BDNF. Another potential association was observed for rs13306221 (χ(2)  = 4.316, p = 0.038, OR = 1.604, 95% CI = 1.024-2.512) in the promoter region of the BDNF. Strong linkage disequilibrium was observed in block 1 (D' > 0.9). Significantly more G-G-G haplotypes in block 1 were found in children with asthma.

These findings point to a role for BDNF polymorphisms in Chinese Han children with asthma and may inform future genetic or biological studies on childhood asthma.