TY - JOUR T1 - Admixture mapping identifies novel loci for obstructive sleep apnea in Hispanic/Latino Americans. JF - Hum Mol Genet Y1 - 2019 A1 - Wang, Heming A1 - Cade, Brian E A1 - Sofer, Tamar A1 - Sands, Scott A A1 - Chen, Han A1 - Browning, Sharon R A1 - Stilp, Adrienne M A1 - Louie, Tin L A1 - Thornton, Timothy A A1 - Johnson, W Craig A1 - Below, Jennifer E A1 - Conomos, Matthew P A1 - Evans, Daniel S A1 - Gharib, Sina A A1 - Guo, Xiuqing A1 - Wood, Alexis C A1 - Mei, Hao A1 - Yaffe, Kristine A1 - Loredo, Jose S A1 - Ramos, Alberto R A1 - Barrett-Connor, Elizabeth A1 - Ancoli-Israel, Sonia A1 - Zee, Phyllis C A1 - Arens, Raanan A1 - Shah, Neomi A A1 - Taylor, Kent D A1 - Tranah, Gregory J A1 - Stone, Katie L A1 - Hanis, Craig L A1 - Wilson, James G A1 - Gottlieb, Daniel J A1 - Patel, Sanjay R A1 - Rice, Ken A1 - Post, Wendy S A1 - Rotter, Jerome I A1 - Sunyaev, Shamil R A1 - Cai, Jianwen A1 - Lin, Xihong A1 - Purcell, Shaun M A1 - Laurie, Cathy C A1 - Saxena, Richa A1 - Redline, Susan A1 - Zhu, Xiaofeng AB -

Obstructive sleep apnea (OSA) is a common disorder associated with increased risk of cardiovascular disease and mortality. Its prevalence and severity vary across ancestral background. Although OSA traits are heritable, few genetic associations have been identified. To identify genetic regions associated with OSA and improve statistical power, we applied admixture mapping on three primary OSA traits [the apnea hypopnea index (AHI), overnight average oxyhemoglobin saturation (SaO2) and percentage time SaO2 < 90%] and a secondary trait (respiratory event duration) in a Hispanic/Latino American population study of 11 575 individuals with significant variation in ancestral background. Linear mixed models were performed using previously inferred African, European and Amerindian local genetic ancestry markers. Global African ancestry was associated with a lower AHI, higher SaO2 and shorter event duration. Admixture mapping analysis of the primary OSA traits identified local African ancestry at the chromosomal region 2q37 as genome-wide significantly associated with AHI (P < 5.7 × 10-5), and European and Amerindian ancestries at 18q21 suggestively associated with both AHI and percentage time SaO2 < 90% (P < 10-3). Follow-up joint ancestry-SNP association analyses identified novel variants in ferrochelatase (FECH), significantly associated with AHI and percentage time SaO2 < 90% after adjusting for multiple tests (P < 8 × 10-6). These signals contributed to the admixture mapping associations and were replicated in independent cohorts. In this first admixture mapping study of OSA, novel associations with variants in the iron/heme metabolism pathway suggest a role for iron in influencing respiratory traits underlying OSA.

VL - 28 IS - 4 ER -