Genetic linkage occurs when particular genetic loci or
alleles for genes are inherited jointly. Genetic loci on the same chromosome are physically connected and tend to segregate together during
meiosis, and are thus genetically linked. Alleles for genes on different chromosomes are usually not linked, due to
independent assortment of chromosomes during
meiosis.
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Logarithm of the odds favoring linkage obtained from the statistical analysis of linkage. The lod score (Z) of +3 is considered evidence for linkage.