Category: Uncategorized

ONGOING Y CHROMOSOME EVOLUTION. "Will it be replaced by some different gene and chromosome? And if so, will this unleash a new round of hominid speciation? We may have to wait another 4.6 million years to find out." https://lnkd.in/ehjz378 View in LinkedIn

HUMAN CONSEQUENCE? "What does this mean for our own lineage? The primate Y seems to be more stable than the rodent Y. But if it continues to degrade at the same rate, it will disappear in about 4.6 million years." https://lnkd.in/ehjz378 View in LinkedIn

SO ENDS the first weekend on the topic of the impact of viruses on the evolution of life. Still considered by many biologists to be just rough pieces of genetic material not worthy of inclusion in the tree of life, there are some who propose a very central role for viruses in the evolution of life. This seems to be a case of not seeing the wood for the trees, bogged down in details, or our mesmerized fixation on the pointing finger, rather than on what it points at. View in LinkedIn

PERMANENT HITCHHIKERS. “After they have entered a cell, viruses become part of the genetic information of the host cell, and all of its progeny are forever changed.” https://lnkd.in/guhpmyR View in LinkedIn

PURIFYING SELECTION. "In plants, however, few deleterious changes may occur in Y-linked alleles, because a high proportion of genes are expressed in the haploid pollen, and, if these genes have important functions during pollination, they may experience strong purifying selection against sequence changes that impair their functions." https://lnkd.in/exrSaeb View in LinkedIn

EXTREME DIVERSITY. “Viruses are the most diverse entities on our planet.” https://lnkd.in/guhpmyR View in LinkedIn

SMALL POPULATION AND MUTATIONS. "The reduced effective population size allows deleterious mutations in functional sequences to increase in frequency in the population, or become fixed, causing deterioration of the sequences." https://lnkd.in/exrSaeb View in LinkedIn

THE KING. “It is the virus that is king of the jungle.” https://lnkd.in/guhpmyR View in LinkedIn

POPULATION IMPACT. "In genome regions with suppressed recombination, selection acting on either advantageous or disadvantageous mutations in the region affects all linked variants. This effectively restricts the size of the population, compared with the rest of the species’ genome, because some genotypes fail to reproduce. The effective population size can be considerably reduced for a Y chromosome that still carries many functional sequences." https://lnkd.in/exrSaeb View in LinkedIn

EVOLUTION. “Viruses are the leading edge of evolution.” https://lnkd.in/guhpmyR View in LinkedIn