Drosophila selected for starvation resistance exhibit characteristics of obesity, metabolic disorder, and cardiac dysfunction.
Several Drosophila populations selected for starvation resistance for over 80 generations have been established. The flies in these lines exhibit developmental delay: a prolonged larval stage allows storage of excess nutrients, which are synthesized into lipids. Adult exhibit phenotypes characteristic of obesity and metabolic disorder, including high levels of lipid storage and depressed metabolic rate accompanied by low activity levels, poor flight performance, and low fecundity; dilated cardiomyopathy and excess sleep are also observed. GWAS analyses have identified over 380 candidate genes potentially under selection in these lines; results suggest multiple mechanisms of adaptation.
In a second study, ten large outbred Drosophila populations have been selected for increased starvation resistance. The selection regime also improved desiccation resistance, water content, and glycogen content among these populations. In addition to increases in lipid content, cardiac dysfunctions and decreased adult lifespan are observed. Genomic analysis revealed a large number of single nucleotide polymorphisms across the genome that changed in frequency as a result of selection.
[updated Feb. 2021 by FlyBase; FBrf0222196]
Obesity is an abnormal accumulation of body fat, usually 20% or more over an individual's ideal body weight. Obesity is associated with increased risk of illness, disability, and death. (http://medical-dictionary.thefreedictionary.com/obesity).
The development of obesity is recognized as having both genetic and environmental components (https://www.sciencelearn.org.nz/resources/203-obesity-genetic-or-environmental).
