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LOH (Loss of Heterozygosity)

updated: July 1, 2022

Definition

LOH (short for “loss of heterozygosity”) refers to a type of mutation that results in the loss of one copy of a segment of DNA (typically containing a gene or group of genes). For most parts of the genome, human cells have two copies of any genomic segment — one from each parent — so in the case of LOH, only one copy would still be present.