The effect of apol i popr otei n(a)-, apol i popr otei n E-, and apol i popr otei n A 4-pol ymor phi sms on quanti tati ve l i popr otei n(a) concentr ati ons

The effects of apol i popr otei n (a), apol i popr otei n-E, and apol i popr otei n-A 4 i sofor ms on quanti tati ve l i popr otei n(a) [Lp(a)] l evel s w er e assessed i n a sampl e of 142 Dutch fami l i es consi sti ng of tw o parents and their adolescent twin offspring. A total heritability of 95% w as esti mated for pl asma Lp(a) concentr ati ons. The l ar gest par t of thi s her i tability was due to the apo(a) l ocus w hi ch expl ai ned 61% of the total var i ance i n Lp(a) l evel s. The patter n of familial correlations for the r esi dual par t of the Lp(a) var i ance that coul d not be attr i buted to the apo(a) i sofor ms, suggested geneti c i nfl uences on the r esi dual var i ance. We addr essed the questi on w hether thi s r esi dual geneti c var i ance coul d be ascr i bed to the apoE or the apoA 4 l ocus. A si mul taneous anal ysi s of al l thr ee l oci show ed that both the apoE and the apoA 4 pol ymor phi sm di d not contr i bute si gni fi cantl y to Lp(a) var i ati on. Twin Research (2000) 3, 152-158