Blood samples were collected from 18 individuals (8 affected individuals) who all signed a consent form, which was approved by the ethics review board of the Centre Hospitalier Affilié Universitaire de Québec. Phenotypic details of these family members have been described previously.5 A 550-marker, 8-cM whole-genome scan was performed on DNA samples from 10 individuals by deCODE Genetics (Reykjavík, Iceland). Genome scan results were analyzed using Genehunter, version 2.1 (Whitehead Institute, Cambridge, Massachusetts), with an autosomal dominant mode of inheritance, a disease frequency of 1 in 10 000, 90% disease penetrance, equal allele frequencies, and equal male-to-female recombination rates. Subsequent 2-point analysis was performed using the MLINK program from the LINKMAP software package (GSF Software, Coral Gables, Florida).6 Additional markers were genotyped by polymerase chain reaction using radiolabeled α-sulfur-35-2′-deoxyadenosine 5′-triphosphate and were loaded on denaturing polyacrylamide gels, 6%. Polymerase chain reactions were performed using 50 ng of DNA and amplified on Perkin Elmer 9600 thermocyclers (Global Medical Instrumentation, Ramsey, Minnesota) using the following protocol: DNA melting at 94°C for 5 minutes followed by 30 replication cycles (30 seconds at 72°C, 40 seconds at 55°C, and 40 seconds at 72°C) and a 10-minute final extension step at 72°C. Polymerase chain reaction products were sequenced at the Genome Quebec Centre for Innovation.