Can mitochondrial DNA be passed through Father?
A tenet of elementary biology is that mitochondria — the cell's powerhouses — and their DNA are inherited exclusively from mothers. A provocative study suggests that fathers also occasionally contribute.
The mitochondria have lost their autonomy but retained their own DNA, called mtDNA, which mainly contains genes required for energy production. While the majority of our DNA is inherited in equal measure from mother and father, mtDNA comes only from the mother.
Typically, humans inherit mitochondria and mitochondrial DNA from their mothers only. But using sequencing data from the mitochondrial genomes of members from three unrelated families, researchers have identified 17 individuals who inherited mtDNA from both parents.
Their results show that mitochondrial DNA is stably transmitted from mothers to their offspring only. This clonal inheritance indeed makes mitochondrial DNA suitable for use in evolutionary studies. Scientists have argued whether or not the often-studied mitochondrial DNA molecule is clonally inherited.
If the father passes on an X chromosome, the baby will be genetically female, and if the father passes on a Y chromosome, the baby will be genetically male.
In the human spermatozoa, one copy of mtDNA is present in one mitochondrion on average. The sperm mtDNA sequence is identical to that of the somatic cells, but the DNA repairing activity in the sperm is less than that in the somatic cells, or is absent altogether.
Unlike nuclear DNA, which is passed down from both the mother and the father, mitochondrial DNA is inherited exclusively from the mother.
Giving a whole new meaning to "pregnancy brain," a new study shows that male DNA—likely left over from pregnancy with a male fetus—can persist in a woman's brain throughout her life.
Patterns of Genetic Transmission
An individual's mitochondrial genome is entirely derived from the mother because sperm contain relatively few mitochondria, and these are degradated after fertilization.
Fathers Can Pass Mitochondrial DNA to Children
Researchers identify unique cases in which people inherited mitochondrial DNA not just from their mother but also from their father.
Can father's mitochondrial DNA benefit hybrids?
Hybrids, for instance, could benefit from having mitochondrial input from both distantly-related parents so that genes and proteins from this organelle can interact effectively with those from the nuclear genome.
Mitochondrial DNA carries characteristics inherited from a mother in both male and female offspring. Thus, siblings from the same mother have the same mitochondrial DNA. In fact, any two people will have an identical mitochondrial DNA sequence if they are related by an unbroken maternal lineage.
The mitochondrial genome is believed to be maternally inherited in many eukaryotes. Sperm-derived paternal mitochondria enter the oocyte cytoplasm upon fertilization and then normally disappear during early embryogenesis.
Even though everyone on Earth living today has inherited his or her mtDNA from one person who lived long ago, our mtDNA is not exactly alike. Random mutations have altered the genetic code over the millennia.
The mitochondria in sperm cells are lost during fertilization, hence the zygote only inherit the mitochondria from the egg.
Patterns of Genetic Transmission
An individual's mitochondrial genome is entirely derived from the mother because sperm contain relatively few mitochondria, and these are degradated after fertilization.
However, testing the mitochondrial genome can prove only if two individuals are related by common descent through maternal lines only from a common ancestor and is, thus, of limited value (i.e., it could not be used to test for paternity).
Mitochondrial DNA is the circular chromosome found inside the cellular organelles called mitochondria. Located in the cytoplasm, mitochondria are the site of the cell's energy production and other metabolic functions. Offspring inherit mitochondria — and as a result mitochondrial DNA — from their mother.
Hybrids, for instance, could benefit from having mitochondrial input from both distantly-related parents so that genes and proteins from this organelle can interact effectively with those from the nuclear genome.