title: Reduced recombination rate on chromosomes 21 that have undergone nondisjunction.
mesh_terms: D002874:Chromosome Mapping; D002891:Chromosomes, Human, Pair 21; D004247:DNA / Q000378:metabolism; D004262:DNA Restriction Enzymes; D004314:Down Syndrome / Q000235:genetics*; D008040:Genetic Linkage; D006801:Humans; D009630:Nondisjunction, Genetic; D011110:Polymorphism, Genetic
chemical_list: D004247:DNA; D004262:DNA Restriction Enzymes