Multipoint analysis for radiation hybrid mapping.

Radiation hybrid mapping is a somatic cell genetic technique that permits construction of fine-structure maps of human chromosomes. Radiation hybrid mapping uses X-ray breakage of chromosomes to order genetic loci and to estimate distances between them. Cox and colleagues described radiation hybrid mapping and derived methods for locus ordering based on two-point statistical analysis of radiation hybrid mapping data. In this paper, I describe alternative non-parametric and likelihood methods for radiation hybrid mapping that make use of information on many loci simultaneously, and efficiently include information on partially typed radiation hybrids. Locus orders are selected by minimum number of obligate chromosome breaks or maximum likelihood. I demonstrate the utility of these methods with an application to data on 14 markers and 99 hybrids for human chromosome 21.