Abstract
Mosaic loss of chromosome Y (mLOY), the most common somatic mutation, prompts fibrotic heart diseases. We hypothesized that it accelerates atrial fibrillation (AF) and contributes to its sex disparity. A total of 214,405 male participants from the UK Biobank without prevalent AF were included, with a median follow-up of 14.31 years. mLOY was associated with a 16% higher AF risk, with 9.6% and 6.4% of the association mediated by neutrophils and monocytes. AF risk of males with mLOY was 98% higher than that of matched females. Thus, mLOY is associated with a slightly increased AF risk, and might partly contribute to sex disparity of AF.