obtained from multiple sources within each family detailed information on pedigrees can be found at hoffman et al j allergy clin immunol 108 615 620 2001 incorporated by reference the individual names and pedigree structures were evaluated extensively for relatedness between families no relationship was ascertained representative segments of the pedigrees are presented in fig4 filled squares represent afflicted males and filled circles afflicted females unaffected individuals are represented by open figures the pedigrees demonstrate an autosomal dominant inheritance pattern with near complete penetrance and a transmission rate of 50 the earliest affected ancestors lived in the 17 th century as noted supra there was no evidence of relatedness between families based upon names or pedigree structure however members of the first three families share a legend concerning the origin of the disorder relating to a healthy man who had a prolonged life threatening exposure to cold water following the exposure the individual developed symptoms of fcas and passed them onto offspring following the results discussed supra blood samples were taken from 179 members of the four families described above of these 74 were afflicted individuals and 105 were unafflicted standard venipuncture and genomic dna isolation techniques were used clones from the fcas locus were identified using oligonucleotides derived from genetic markers that had been marked previously these oligonucleotides were labeled with 32 p and were hybridized to rpci 11bac in accordance with shizuya et al.