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Not completely. For example mitochondrial DNA is totally separate from regular DNA, and it's passed exclusively mother to offspring. It's the old bootstrapping

by 323 4y ago

Not completely. For example mitochondrial DNA is totally separate from regular DNA, and it's passed exclusively mother to offspring. It's the old bootstrapping problem - how do you get a running C compiler from code if you don't already have a running C compiler? There is no example in nature where you get a fully functional cell starting exclusively from DNA.

njarboe 4y ago
"it's passed exclusively mother to offspring" As in most absolute statements, this may not be completely true. Sperm has some mitochondria that likely is incorporated into the zygote.[1] [1] https://en.wikipedia.org/wiki/Paternal_mtDNA_transmission https://en.wikipedia.org/wiki/Paternal_mtDNA_transmission
- tibbydudeza 4y ago
  Afaik the mitochondria of the sperm cell is located in the tail to power it which then gets detached from the head just after it has borrowed into the egg ???.
  - njarboe 4y ago
    From the Wikipedia page (read the original source for details): The controversy about human paternal leakage was summed up in the 1996 study Misconceptions about mitochondria and mammalian fertilization: Implications for theories on human evolution, which was peer-reviewed and printed in Proceedings of the National Academy of Sciences.[15] According to the study's abstract: In vertebrates, inheritance of mitochondria is thought to be predominantly maternal, and mitochondrial DNA analysis has become a standard taxonomic tool. In accordance with the prevailing view of strict maternal inheritance, many sources assert that during fertilization, the sperm tail, with its mitochondria, gets excluded from the embryo. This is incorrect. In the majority of mammals—including humans—the midpiece mitochondria can be identified in the embryo even though their ultimate fate is unknown. The "missing mitochondria" story seems to have survived—and proliferated—unchallenged in a time of contention between hypotheses of human origins, because it supports the "African Eve" model of recent radiation of Homo sapiens out of Africa. [15] Ankel-Simons F, Cummins JM (November 1996). "Misconceptions about mitochondria and mammalian fertilization: Implications for theories on human evolution". Proc. Natl. Acad. Sci. U.S.A. 93 (24): 13859–63. Bibcode:1996PNAS...9313859A. doi:10.1073/pnas.93.24.13859. PMC 19448. PMID 8943026.

by 323 4y ago

njarboe 4y ago

"it's passed exclusively mother to offspring" As in most absolute statements, this may not be completely true. Sperm has some mitochondria that likely is incorporated into the zygote.[1] [1] https://en.wikipedia.org/wiki/Paternal_mtDNA_transmission https://en.wikipedia.org/wiki/Paternal_mtDNA_transmission

tibbydudeza 4y ago
Afaik the mitochondria of the sperm cell is located in the tail to power it which then gets detached from the head just after it has borrowed into the egg ???.
- njarboe 4y ago
  From the Wikipedia page (read the original source for details): The controversy about human paternal leakage was summed up in the 1996 study Misconceptions about mitochondria and mammalian fertilization: Implications for theories on human evolution, which was peer-reviewed and printed in Proceedings of the National Academy of Sciences.[15] According to the study's abstract: In vertebrates, inheritance of mitochondria is thought to be predominantly maternal, and mitochondrial DNA analysis has become a standard taxonomic tool. In accordance with the prevailing view of strict maternal inheritance, many sources assert that during fertilization, the sperm tail, with its mitochondria, gets excluded from the embryo. This is incorrect. In the majority of mammals—including humans—the midpiece mitochondria can be identified in the embryo even though their ultimate fate is unknown. The "missing mitochondria" story seems to have survived—and proliferated—unchallenged in a time of contention between hypotheses of human origins, because it supports the "African Eve" model of recent radiation of Homo sapiens out of Africa. [15] Ankel-Simons F, Cummins JM (November 1996). "Misconceptions about mitochondria and mammalian fertilization: Implications for theories on human evolution". Proc. Natl. Acad. Sci. U.S.A. 93 (24): 13859–63. Bibcode:1996PNAS...9313859A. doi:10.1073/pnas.93.24.13859. PMC 19448. PMID 8943026.