Nat Genet: Single-gene disease may not be as simple as scientists think

Oct 19, 2020 // -- Traditionally, geneticists have classified diseases as "simple" and "complex" diseases, the former being caused by a single gene mutation and the latter by multiple genetic mutations, but a recent study published in the international journal Nature Genetics found that many diseases may actually fall somewhere between "simple" and "complex" diseases.
Photo Source: CC0 Public Domain For years, scientists studying the genome of a patient's body have observed genetic burdens or additional genetic mutations in the patient's body that promote the effects of disease-caused gene mutations and make them stronger or weaker;
scientists now use a large number of genetic and functional means to prove the existence of a single gene-induced burden of disease.
the study, researchers focused on hundreds of patients with Bardet-Biedl syndrome (BBS), a disease that affects the body's cognitive function, vision, kidney function and weight regulation, and, crucially, all of them have been diagnosed with BBS because they carry a mutation in one of 25 genes known to be associated with the disease. When the researchers analyzed all known BBS genes in these patients, they found that they carried more than three times as many additional mutations, patterns that more easily linked researchers to genetic disorders with complex characteristics, such as Alzheimer's disease and type 2 diabetes. But it is also driven by its position in the disease network.
The results of this paper also suggest that in a clinical setting, the type of genetic data should be returned to the patient's study, and researcher Dr. Nico Katsanis says we need to expand our current study to look for answers beyond a single pathogenic gene, and we've always known that the causality of disease may not be binary, but it's continuous, but we don't have the evidence and tools to test it.'
researchers now hope to gain a deeper understanding and prediction of how disease occurs.
later this year, researchers will apply the findings to a range of other diseases, while also focusing on a network of genetic mutations that accelerate the severity of the disease.
original source: Maria Kousi, Onuralp Söylemez, Aysegül Ozanturk, et al. Evidence for secondary-variant genetic burden and non-random distribution across biological modules in a recessive ciliopathy, Nature Genetics (2020). DOI:10.1038/s41588-020-0707-1