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Angela
27-11-18, 19:09
This is extraordinary and revolutionary. If true, does it call into question the use of the mtDna lineages for population genetics purposes?

See:

"Biparental Inheritance of Mitochondrial DNA in Humans"Shiyu Luo et al




http://www.pnas.org/content/early/2018/11/21/1810946115

"SignificanceThe energy-producing organelle mitochondrion contains its own compact genome, which is separate from the nuclear genome. In nearly all mammals, this mitochondrial genome is inherited exclusively from the mother, and transmission of paternal mitochondria or mitochondrial DNA (mtDNA) has not been convincingly demonstrated in humans. In this paper, we have uncovered multiple instances of biparental inheritance of mtDNA spanning three unrelated multiple generation families, a result confirmed by independent sequencing across multiple unrelated laboratories with different methodologies. Surprisingly, this pattern of inheritance appears to be determined in an autosomal dominantlike manner. This paper profoundly alters a widespread belief about mitochondrial inheritance and potentially opens a novel field in mitochondrial medicine.

AbstractAlthough there has been considerable debate about whether paternal mitochondrial DNA (mtDNA) transmission may coexist with maternal transmission of mtDNA, it is generally believed that mitochondria and mtDNA are exclusively maternally inherited in humans. Here, we identified three unrelated multigeneration families with a high level of mtDNA heteroplasmy (ranging from 24 to 76%) in a total of 17 individuals. Heteroplasmy of mtDNA was independently examined by high-depth whole mtDNA sequencing analysis in our research laboratory and in two Clinical Laboratory Improvement Amendments and College of American Pathologists-accredited laboratories using multiple approaches. A comprehensive exploration of mtDNA segregation in these families shows biparental mtDNA transmission with an autosomal dominantlike inheritance mode. Our results suggest that, although the central dogma of maternal inheritance of mtDNA remains valid, there are some exceptional cases where paternal mtDNA could be passed to the offspring. Elucidating the molecular mechanism for this unusual mode of inheritance will provide new insights into how mtDNA is passed on from parent to offspring and may even lead to the development of new avenues for the therapeutic treatment for pathogenic mtDNA transmission."

hrvclv
28-11-18, 14:48
A scientific breakthrough, in a way. But not really good news. What was clear and reliable so far will now be tinged with doubt.

Maciamo
29-11-18, 09:47
This is dumbfounding. I am curious as to which mtDNA haplogroups are involved and whether some mutations within mitochondria may make them more likely to be passed on paternally.

The abstract says that biparental mtDNA transmission has an autosomal dominant-like inheritance mode. Does that mean that a mutation on one of the chromosomes may be responsible for it? I can imagine that it may have something to do with the permeability of the ovum cell wall to sperm or the process of removing mtDNA from spermatozoa. If this is compromised, then it would allow the sperm's mitochondria to mix with the ovum's mitochondria, thus causing heteroplasmy.

MOESAN
30-11-18, 23:56
I suppose it is rather a seldom phenomena.
When gener unbalanced admixtures of pops have been explorated in past, and when the Y-DNA and mt-DNA distribution (as a whole) of both pops taking part in these admixtures were different enough, we see an opposition in origin between Y-haplos and mt-haplos, the total auDNA is a more or less mean midst both pops and the X-DNA tends more towards the pop giving the mt- markers; in this case, the % dominance of the mt-haplos is stronger than the % dominance in X-auDNA: so, at least, mt-DNA recombines neatly less than does X-auDNA... Unseasy to me to explain it in correct english! Sorry.

Regio X
01-12-18, 01:07
This is dumbfounding. I am curious as to which mtDNA haplogroups are involved and whether some mutations within mitochondria may make them more likely to be passed on paternally.

The abstract says that biparental mtDNA transmission has an autosomal dominant-like inheritance mode. Does that mean that a mutation on one of the chromosomes may be responsible for it? I can imagine that it may have something to do with the permeability of the ovum cell wall to sperm or the process of removing mtDNA from spermatozoa. If this is compromised, then it would allow the sperm's mitochondria to mix with the ovum's mitochondria, thus causing heteroplasmy.See this: https://thegeneticgenealogist.com/2018/11/26/can-mtdna-really-come-dad/

MOESAN
01-12-18, 11:39
See this: https://thegeneticgenealogist.com/2018/11/26/can-mtdna-really-come-dad/

Thanks, Regio X - it's very helpful to prevent "drifted" interpretations.

spruithean
01-12-18, 19:43
Yeah this might be groundbreaking but it is not panic worthy, especially considering the rarity and so far, paternal inheritance, heteroplasmy and mitochondrial disease link. This is rare and at worst affects timing estimations for mt-Eve.

gidai
27-01-19, 15:45
Do you know that some of these people have offspring that carries a single maternal mtDNA ?
I imagine that if it were a genetically inherited predisposition, then the multi-mtDNA bearers would have descendants that probably would accumulate for each generation new mtDNAs! Probably we would now have carriers with 3, 4, 5 or more mtDNA haplogroups?! That's why I think it's maybe an accident than something genetically inherited.