We have recently submitted a manuscript for publication as well as an abstract to a human genome variation meeting. The work represents an application of the MGD hypothesis in solving major real world biomedical problems. The results confirm the MGD hypothesis and invalidate the neutral theory that has prevailed for nearly half of a century. The flawed neutral theory has no real world relevance to major biomed problems and no neutral theory experts are known to have contributed anything to research of major biomedical importance (not Kimura, not Ayala, not Nei, not Blair, not Avise, not Felsenstein). In contrast, the MGD hypothesis can and will survive even without relying on its value to evolution research. Much of our ongoing research have nothing to do with evolution. Stay tuned for more of our results on the genetic basis of complex traits and complex diseases about which the neutral paradigm has absolutely no clues.
Random
enrichment of minor alleles of common SNPs affects complex traits and diseases.
Dejian Yuan1#, and Zuobin Zhu1#, Xiaohua Tan1,
Jie Liang1, Ceng Zeng1, Jiegen Zhang2, Jun
Chen2, Long Ma1, Ayca Dogan3, Gudrun Brockmann3, Oliver Goldmann4, Eva Medina4, Xian Man1,
Ke Yi1, Yanke Li1, Qing Lu1, Yimin Huang1,
Dapeng Wang5, Jun Yu5, Hui Guo1, Kun Xia1, and Shi Huang1*
1State Key Laboratory of Medical Genetics, Central South
University, 110 Xiangya Road, Changsha, Hunan 410078, China; 2High Performance Computing Center, Modern Educational Technology Center,
New Campus, Central South University, Changsha, Hunan
410083, China. 3Department
of Crop and Animal Sciences, Faculty of Agriculture and Horticulture,
Humboldt-Universität zu Berlin, Invalidenstraße 42, 10115 Berlin, Germany; 4Infection Immunology Group, HZI – Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig,
Germany; 5CAS
Key Laboratory of Genome Sciences and Information, Beijing Institute of
Genomics, Chinese Academy of Sciences, Beijing 100029, PR China; Graduate University of Chinese Academy
of Sciences, Beijing 100049, PR China.
#These authors contributed equally to this work.
The prevailing null hypothesis in
population genetics and molecular evolution posits that most common SNPs are neutral
but this has yet to be formally tested by experimental science. We employed two strategies to determine
whether the minor alleles (MAs) of common SNPs are minor because of natural
selection. First, we analyzed multiple
panels of genetic reference populations or recombinant inbred
lines (RILs) in model
organisms (yeast, worm, fly, mouse, and rat), and identified the MAs of common SNPs in each panel and the fraction of MAs that each
strain carries. We measured the brood
size of 104 C. elegans RILs and did
genotype-phenotype correlation analysis for the brood trait as well as for
~4700 published and unpublished traits for various RIL panels archived at
GeneNetwork. Although beneficial to immunity as is expected, more MAs correlated significantly with poor measurements in many adaptive traits,
including reproductive fitness, life span, tumor susceptibility, anxiety, depression,
startle response, and learning and memory. In addition, more MAs were significantly linked with sensitivity to alcohol, methamphetamine,
cocaine, pain, and antipsychotic drugs, and levels in glucose, resistin, insulin,
IL-17, iron, and dopamine. Random enrichment of MAs
of common SNPs accounted for as much as 49% of total trait variation in some
phenotypes in RILs such as transferrin saturation and food intake. The majority of the ~4700 traits examined did not significantly correlate with MAs, including blood pressure and
morphine response. Different MA-linked traits may
or may not share the same set of MAs with related traits sharing more MAs than
non-related traits. Second, we analyzed 21 published
GWAS datasets of common diseases and identified the MAs of common SNPs in each
control population and the fraction of MAs each control or case carries. In Europeans or European Americans, more MAs were significantly and
repeatedly linked with type
2 diabetes, Parkinson’s disease, psychiatric disorders, autoimmune diseases, alcohol and cocaine addictions, lung cancer, less
life span, and lower education level achieved, but not hypertension and opiate
and marijuana addictions. Thus, the effects of
excess MAs in humans are remarkably similar to those in model organisms, suggesting
that the link between excess MAs and diseases/traits in humans is causal since
it can be replicated in model organisms.
These data indicate
that most SNPs in any species are functional or under Darwinian natural selection and open a new avenue of inquiry into the genetic
basis of complex traits/diseases. They confirm a
self-evident intuition in construction that any system of great order can allow
some random errors/noises in building blocks but only to a limit.