A 2019 study by the Berger lab has revealed that compound haploinsufficiency of two genes; Dok2 and Dusp4 promotes lung tumorigenesis. In layman’s terms, if these two genes are not adequately expressed, then these conditions promote cell proliferation, which gives rise to tumors in the lung tissue. The study used mouse models with co-deletions of the genes on chromosome 8p. This is on the basis of the fact that DOK2 and DUSP4 have been found to be co-deleted in about half of sampled human lung adenocarcinomas. In turn, the researchers used mouse orthologs (the mouse version of the human gene) in the study. Said haploinsufficiency resulted in the formation of lung tumors with high incidence and short latency. It also activated MAPK signalling and promoted cell proliferation. When the genes were restored, then this chain of events was suppressed. If only one of the pair is deleted, then the results are not as severe. With these findings, the research team has found experimental support for the hypothesis that compound haploinsuffiency due to broad-scale chromosome deletions account for a driving force behind tumorigenesis.
Here is the article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6307955/