The high-LD interval (A, dashed box) was fully sequenced in two chromosomes, leading to the identification of candidate causal sites; resequencing of these variants in CEPH trios was used to resolve LD structure within this interval (B). Of all homozygous variants, those that are in high or complete r² with 3435C>T (•) are the most likely candidates to be causal; heterozygous mutations (▵) result in decreased r². (○) The cases where a new set of CEPH trios was used to calculate r² compared to the rest of the study. Bars indicate the Bayesian 95% credible intervals calculated by the method described in Supplemental materials.