The present invention provides methods for analyzing large nucleic acids including chromosomes and chromosomal fragments. In one aspect, the present invention provides a method of nucleic acid analysis comprising the steps of (a) obtaining a sample of nucleic acid comprising at least one chromosome or fragment greater than about 1000 base pairs in length and containing a target region; (b) creating an emulsion in which each drop of the emulsion contains an average of between about 0-2, 0-1.75, 0-1.5, 0-1.0, 0-0.75, 0-0.5, or fewer chromosomes or fragments of step (a), (c) performing emulsion PCR, (d) quantifying the number of emulsion droplets containing amplified nucleic acid from the target region; (e) calculating the ratio of droplets containing amplified nucleic acid from the target region to total droplets; and (f) comparing the ratio of step (e) to a reference ratio representing a known genotype.