Article

Mitochondrial haplogroups associated with Japanese centenarians, Alzheimer's patients, Parkinson's patients, type 2 diabetic patients and healthy non-obese young males.

Toyo University, Ouragun Itakuracho, Gunma 374-0193, Japan.
Journal of Genetics and Genomics (Impact Factor: 2.92). 08/2009; 36(7):425-34. DOI: 10.1016/S1673-8527(08)60132-0
Source: PubMed

ABSTRACT The relationships between five classes of Japanese people (i.e., 96 centenarians, 96 Alzheimer's disease (AD) patients, 96 Parkinson's disease (PD) patients, 96 type 2 diabetic (T2D) patients, and 96 healthy non-obese young males) and their mitochondrial single nucleotide polymorphism (mtSNP) frequencies at individual mtDNA positions of the entire mitochondrial genome were examined using the radial basis function (RBF) network and the modified method. New findings of mitochondrial haplogroups were obtained for individual classes. The five classes of people were associated with the following haplogroups: Japanese centenarians-M7b2, D4b2a, and B5b; Japanese AD patients-G2a, B4c1, and N9b1; Japanese PD patients-M7b2, B4e, and B5b; Japanese T2D patients-B5b, M8a1, G, D4, and F1; and Japanese healthy non-obese young males- D4g and D4b1b. From the points of common haplogroups among the five classes, the centenarians have the common haplogroups M7b2 and B5b with the PD patients and common haplogroup B5b with the T2D patients. In addition, the 112 Japanese semi-supercentenarians (over 105 years old) recently reported were also examined by the method proposed. The results obtained were the haplogroups D4a, B4c1a, M7b2, F1, M1, and B5b. These results are different from the previously reported haplogroup classifications. As the proposed analysis method can predict a person's mtSNP constitution and the probabilities of becoming a centenarian, AD patient, PD patient, or T2D patient, it may be useful in initial diagnosis of various diseases.

0 Followers
 · 
74 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Most cell functions are carried out by interacting factors, thus underlying the functional importance of genetic interactions between genes, termed epistasis. Epistasis could be under strong selective pressures especially in conditions where the mutation rate of one of the interacting partners notably differs from the other. Accordingly, the order of magnitude higher mitochondrial DNA (mtDNA) mutation rate as compared to the nuclear DNA (nDNA) of all tested animals, should influence systems involving mitochondrial-nuclear (mito-nuclear) interactions. Such is the case of the energy producing oxidative phosphorylation (OXPHOS) and mitochondrial translational machineries which are comprised of factors encoded by both the mtDNA and the nDNA. Additionally, the mitochondrial RNA transcription and mtDNA replication systems are operated by nDNA-encoded proteins that bind mtDNA regulatory elements. As these systems are central to cell life there is strong selection toward mito-nuclear co-evolution to maintain their function. However, it is unclear whether (A) mito-nuclear co-evolution befalls only to retain mitochondrial functions during evolution or, also, (B) serves as an adaptive tool to adjust for the evolving energetic demands as species' complexity increases. As the first step to answer these questions we discuss evidence of both negative and adaptive (positive) selection acting on the mtDNA and nDNA-encoded genes and the effect of both types of selection on mito-nuclear interacting factors. Emphasis is given to the crucial role of recurrent ancient (nodal) mutations in such selective events. We apply this point-of-view to the three available types of mito-nuclear co-evolution: protein-protein (within the OXPHOS system), protein-RNA (mainly within the mitochondrial ribosome), and protein-DNA (at the mitochondrial replication and transcription machineries).
    Frontiers in Genetics 12/2014; 5:448. DOI:10.3389/fgene.2014.00448
  • [Show abstract] [Hide abstract]
    ABSTRACT: The accumulation of mutations in mitochondrial DNA is a widely recognized mechanism for aging and age related diseases. However, studies indicate that some mutations could be beneficial to longevity by slowing down the function of the electron transport chain, reducing free radical production. In this study, we re-sequenced the entire mitochondrial DNA from 50 individuals and examined aging-related variations in the Turkish population. We evaluated sequence data by comparing whole SNP frequencies, individual SNP frequencies, the effect of SNPs, SNP accumulation in certain mtDNA regions and haplotype profiles between elderly and control groups. The frequency of total mitochondrial SNPs was significantly higher in nonagenarians than controls (p=0.0094). Furthermore, non-coding, synonymous and tRNA mutations were more prevalent in the 90+ group compared to controls (p=0.0001, p<0.001, p=0.0096, respectively). A73G and C152T polymorphisms were significantly associated with longevity in the Turkish population (p=0.0086 and p=0.004, respectively). Additionally, C150T was specific to the 90+ group, but the difference failed to reach statistical significance (p=0.053). We also detected a novel transversion in the ATPase6 gene (C8899A) that was negatively associated with longevity (p=0.0016). Examining the distribution of SNPs among genes and functionally associated gene regions revealed a significant accumulation of mutations in the D-loop region and genes encoding complex I subunits (ND1-6) (p<0.0001, p=0.0302, respectively). Moreover, there was an increase in the non-synonymous mutation frequency of Complex I genes in aged subjects (p<0.0001). Haplotype H was also significantly increased in the control group (p=0.0405). Overall, our findings support a role for mitochondrial genome variations and the functionality of oxidative phosphorylation in longevity. In this report, we sequenced the whole mtDNA of the Turkish population for the first time.
    Mitochondrion 05/2014; DOI:10.1016/j.mito.2014.04.013 · 3.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hepatocellular carcinoma (HCC) is an important cause of death all over the world, more so in Asia and Africa. The representative data on epidemiology of HCC in India is very scanty and cancer is not a reportable disease in India and the cancer registries in India are mostly urban. 45 million people who are suffering from chronic Hepatitis B virus (HBV) infection and approximately 15 million people who are afflicted with chronic Hepatitis C virus (HCV) infection in India. HBV and HCV infection is considered an important etiologic factor in HCC. Positive association between HCC and consumption of alcohol where alcohol contribute as a cofactor for hepatotoxins and hepatitis viruses. Aflatoxin contamination in the diets, Hepatitis B virus infection and liver cirrhosis in Andhra Pradesh, India and direct chronic exposure to aflatoxins was shown to cause liver cirrhosis. Cirrhosis of liver of any cause lead to develop about 70%–90% of HCC. Aflatoxin interact synergistically with Hepatitis B virus (HBV)/Hepatitis C virus (HCV) infection which increase the risk of HCC. HBV infection, HBV infection with Aflatoxin exposure, viral infection and alcohol consumption leading to overt cirrhosis of the liver, alcohol consumption leading to cirrhosis of the liver with viral infection are the predominant risk factor for the development of HCC. HCV and alcohol are also associated with HCC in India. Indians develop diabetes at younger age, Asians have strong genetic susceptibility for type II diabetes. Diabetes mellitus is identified as a risk factor for HCC. Prevention of viral infection by universal vaccination against hepatitis virus, HCC surveillance program, preventing alcoholic liver diseases, fungal contamination of grains and ground crops to prevent basically Aflatoxin exposure are important measures to prevent liver diseases and HCC among those at risk.
    08/2014; 4(Suppl 3). DOI:10.1016/j.jceh.2014.02.155