Figure 1.

Two types of loss of heterozygosity. There are two main types of loss of heterozygosity (LOH), LOH with copy number losses (CNL-LOH) and copy number neutral LOH (CNN-LOH). Mitotic recombination is considered a major contributor to acquired LOH. During cancer progression, tumor cells may lose one allele (here referred to as A) as a consequence of partial chromosome deletion which is defined as LOH with copy number losses (CNL-LOH). CNL-LOH could further undergo recombination using the homolog (here refers as allele B) as a template for correction which is defined as LOH with copy number neutral (CNN-LOH). Here, orange and green regions represent either of two homologous chromosomes.