This package performs a Latent Class Analysis of phenotypic measurements in pedigrees and a model selection based on one of two methods: likelihood-based cross-validation and Bayesian Information Criterion. It computes also individual and triplet child-parents weights in a pedigree using an upward-downward algorithm. It takes into account the familial dependence defined by the pedigree structure by considering that a class of a child depends on his parents classes via triplet-transition probabilities of the classes. The package handles the case where measurements are available on all subjects and the case where measurements are available only on symptomatic (i.e. affected) subjects. Distributions for discrete (or ordinal) and continuous data are currently implemented. The package can deal with missing data.