CHRNA1 and chronic obstructive pulmonary disease: The only significant associations in the Boston Early-Onset COPD families were with the rs8034191 and rs1051730 SNPs at the CHRNA 3/5 locus (p = 0.03 and 0.03 respectively) and the rs1828591 and rs13118928 SNPs at the HHIP locus (p = 0.0025 and 0.0014 respectively) with post bronchodilator FEV1.