[1] Natl Univ Ireland Univ Coll Cork, Dept Biochem, Cork, Ireland
[2] Univ Coll Dublin, Sch Biol & Environm Sci, Dublin, Ireland
[3] Natl Univ Ireland Univ Coll Cork, BioSci Inst, Cork, Ireland
[4] Brigham & Womens Hosp, Dept Med, Div Genet, Boston, MA 02115 USA
[5] Harvard Univ, Sch Med, Boston, MA 02115 USA
[6] Univ Utah, Dept Human Genet, Salt Lake City, UT 84112 USA