Analysis of Huntington disease linkage and age‐of‐onset distributions

Our analysis of the Huntington disease (HD) data set compares four different approaches for dealing with age of onset in HD and their effect on the resulting lod scores and estimates of the recombination fraction. The methods are: estimation of the age of onset curve by the normal distribution using sample mean and variance for ages of onset from affected family members, normal approximation using maximum likelihood which includes information on at-risk individuals, an exponential-type distribution based upon published data, and no adjustment for age of onset - dichotomy assumed.