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paoloferrari
06-18-2017, 01:14 PM
Mitochondrial DNA sequence data reveals association of haplogroup U with psychosis in bipolar disorder

http://www.sciencedirect.com/science/article/pii/S0022395616304459

"Abstract

Converging genetic, postmortem gene-expression, cellular, and neuroimaging data implicate mitochondrial dysfunction in bipolar disorder. This study was conducted to investigate whether mitochondrial DNA (mtDNA) haplogroups and single nucleotide variants (SNVs) are associated with sub-phenotypes of bipolar disorder. MtDNA from 224 patients with Bipolar I disorder (BPI) was sequenced, and association of sequence variations with 3 sub-phenotypes (psychosis, rapid cycling, and adolescent illness onset) was evaluated. Gene-level tests were performed to evaluate overall burden of minor alleles for each phenotype. The haplogroup U was associated with a higher risk of psychosis. Secondary analyses of SNVs provided nominal evidence for association of psychosis with variants in the tRNA, ND4 and ND5 genes. The association of psychosis with ND4 (gene that encodes NADH dehydrogenase 4) was further supported by gene-level analysis. Preliminary analysis of mtDNA sequence data suggests a higher risk of psychosis with the U haplogroup and variation in the ND4 gene implicated in electron transport chain energy regulation. Further investigation of the functional consequences of this mtDNA variation is encouraged."

Saetro
06-18-2017, 07:53 PM
Mitochondrial DNA sequence data reveals association of haplogroup U with psychosis in bipolar disorder

http://www.sciencedirect.com/science/article/pii/S0022395616304459

"Abstract

Converging genetic, postmortem gene-expression, cellular, and neuroimaging data implicate mitochondrial dysfunction in bipolar disorder. This study was conducted to investigate whether mitochondrial DNA (mtDNA) haplogroups and single nucleotide variants (SNVs) are associated with sub-phenotypes of bipolar disorder. MtDNA from 224 patients with Bipolar I disorder (BPI) was sequenced, and association of sequence variations with 3 sub-phenotypes (psychosis, rapid cycling, and adolescent illness onset) was evaluated. Gene-level tests were performed to evaluate overall burden of minor alleles for each phenotype. The haplogroup U was associated with a higher risk of psychosis. Secondary analyses of SNVs provided nominal evidence for association of psychosis with variants in the tRNA, ND4 and ND5 genes. The association of psychosis with ND4 (gene that encodes NADH dehydrogenase 4) was further supported by gene-level analysis. Preliminary analysis of mtDNA sequence data suggests a higher risk of psychosis with the U haplogroup and variation in the ND4 gene implicated in electron transport chain energy regulation. Further investigation of the functional consequences of this mtDNA variation is encouraged."

Bold italics are my highlights.

The key word is "suggests". And the call for further investigation.
Many of these initial associations have proved to be tenuous at best when confronted with more data.
These researchers at least understand that more work is required.

GailT
06-21-2017, 08:08 PM
I can't access the paper but wonder if this might be a false association from small sample size. It would be interesting to know what SNP they think is responsible, Notes from SNPedia:

A11467G: One of 3 Mitochondrial mutations that together define Mitochondrial Haplogroup U, and its descendants. This is a synonymous change that still codes for the exact same amino acid, so it probably has no biological effect.

A12308G is one of the three defining mitochondrial DNA mutations of Haplogroup U. Medically, this is part of the mitochondrial tRNA gene MT-L2, responsible for building mitochondrial proteins containing the amino acid Leucine.

G12372A, . One of the 3 SNPs that defines Mitochondrial Haplogroup U and its descendants. The minor allele is synonymous, so it makes no biological difference.

Baltimore1937
06-22-2017, 05:39 AM
Looks like time for a class-action lawsuit for defaming my U haplogroup. I wonder how much money we U's can make on that.
:beerchug:

Ann Turner
06-22-2017, 08:45 PM
I can't access the paper but wonder if this might be a false association from small sample size. It would be interesting to know what SNP they think is responsible, Notes from SNPedia:

A11467G: One of 3 Mitochondrial mutations that together define Mitochondrial Haplogroup U, and its descendants. This is a synonymous change that still codes for the exact same amino acid, so it probably has no biological effect.

A12308G is one of the three defining mitochondrial DNA mutations of Haplogroup U. Medically, this is part of the mitochondrial tRNA gene MT-L2, responsible for building mitochondrial proteins containing the amino acid Leucine.

G12372A, . One of the 3 SNPs that defines Mitochondrial Haplogroup U and its descendants. The minor allele is synonymous, so it makes no biological difference.
I agree about the small sample size, particularly when they're subdividing it into three different phenotypes and who knows how many different haplogroups.