Year: 2022

DIVERSITY OF MECHANISM. "The mechanisms of how uniparental organelle transmission is achieved are also very diverse. Many different organelle exclusion mechanisms exist, and they can act either before, during or after fertilization." https://lnkd.in/d34vWHz View in LinkedIn

NECESSARY RECOMBINATION. "Uniparental inheritance excludes organelles from sexual recombination. However, recombination is believed to be necessary to allow genomes to escape mutational meltdown, a process known as Muller's ratchet. Uniparental (maternal) organelle transmission should therefore be an evolutionary dead end." https://lnkd.in/d34vWHz View in LinkedIn

NECESSARY FREQUENCY. "It seems possible that sexual recombination of oDNA is widespread and perhaps even a general phenomenon. As paternal leakage of plastids occurs at least occasionally in many, if not all, species, sexual recombination of plastids in seed plants may be limited by the rarity of plastid fusion events." (oDNA = organelle DNA). https://lnkd.in/d34vWHz View in LinkedIn

FRAGMENT FROM NATURE is a contemplation of pleiotropy and a caution on gene-centricity as a singular viewpoint in biology. Non-Mendelian inheritance illustrates non-gene, extra-nuclear means of coding inheritable information. While genomics has transformed the life sciences beyond recognition, there is an emerging picture of subtle and powerful forces far beyond the gene. View in LinkedIn

GRADUAL EVOLUTION. "Since the origin of evolutionary science, biologists have insisted that adaptation is an achingly slow process. ' Natura non facit saltum ' (nature does not take leaps) was a favourite incantation of Charles Darwin. As the combined power of genetic mutation and natural selection became better appreciated in the 1930s and 1940s, theorists solidified a gradualist doctrine: adaptation must rely on innumerable genetic changes, each with effects so small that any attempt to catch them experimentally was considered futile." https://lnkd.in/dAC2mFa View in LinkedIn

"PLEIOTROPY, the way in which a single gene can affect many factors, had been a major rationale behind gradualist dogma." https://lnkd.in/dAC2mFa View in LinkedIn

PLEIOTROPY AND FITNESS. "In evolution, the strength of natural selection on a gene depends on the gene’s pleiotropic effects on traits related to fitness." https://lnkd.in/dw8tEKD View in LinkedIn

BREEDING CONFOUNDED. "In plant or animal breeding, directional pleiotropy is rampant because, when selection is applied to one trait, the mean of many other traits also changes over generations, sometimes in directions that not desirable for the breeder (for example, selecting for increased production may result in reduced reproduction)." https://lnkd.in/dw8tEKD View in LinkedIn

OVERLOOKED IN GENE KNOCKOUTS. "Selection experiments using laboratory species also observed this well over 50 years ago (and it was therefore somewhat puzzling that the mouse knockout community was surprised to observe that induced mutations often had effects on multiple phenotypes)." https://lnkd.in/dw8tEKD View in LinkedIn

MENDELIAN PLEIOTROPY. "In human Mendelian (and clinical) genetics, pleiotropy is observed when a single mutation that causes disease can have multiple features. For example, gene mutations that cause intellectual disability can also result in facial dysmorphology and stunted growth." https://lnkd.in/dw8tEKD View in LinkedIn