Month: September 2022

DARK MATTER. "Despite being ubiquitous, viruses are often called the dark matter of biology as their influence frequently goes unnoticed." https://www.newscientist.com/article/dn27384-virus-hiding-in-our-genome-protects-early-human-embryos/ View in LinkedIn

POST GENOME. "The last 15 years have seen a huge accumulation of data regarding retroviruses and the sequence and structure of their genomes and proteins." https://lnkd.in/eBisbvi View in LinkedIn

RETROVIRUS. "Retroviridae is a family of enveloped viruses that replicate in a host cell through the process of reverse transcription. A retrovirus is a single-stranded positive-sense RNA virus with a DNA intermediate and, as an obligate parasite, targets a host cell. Once inside the host cell cytoplasm, the virus uses its own reverse transcriptase enzyme to produce DNA from its RNA genome — the reverse of the usual pattern, thus retro (backwards)." https://lnkd.in/e3SryN4 View in LinkedIn

VIRAL ARCHAELOLOGY. "The human genome is estimated to contain tens of thousands of copies of human endogenous retroviruses (HERVs) and related sequences, accounting for ∼8% of its sequence content." https://lnkd.in/eW3mbzE View in LinkedIn

READ CAREFULLY. "It turns out that the human genome contains segments of DNA that match pol, env, and gag. Lots of them. Scientists have identified 100,000 pieces of retrovirus DNA in our genes, making up eight percent of the human genome. That’s a huge portion of our DNA when you consider that protein coding genes make up just over one percent of the genome." https://lnkd.in/b3zUsU5 View in LinkedIn

ZOMBIE GRAVEYARD. "Human endogenous retroviruses (HERVs) are normal components of the human genome. They are thought to be remnants of ancient germ line infections by exogenous retroviruses." https://lnkd.in/bNEJmbG View in LinkedIn

INSERTED DNA. "Our ancestors were infected with retroviruses on a regular basis. On rare occasion, a virus infected a sperm or egg and managed to end up in an embryo. Every new cell in the embryo inherited the retrovirus DNA implanted in its genome. And then the embryo grew up into an adult, which then had offspring of its own, and passed the virus DNA on as well." https://lnkd.in/b3zUsU5 View in LinkedIn

MOST INSERTS NOT FIXED. ""The vast majority of EVE insertions never reach fixation, and there are likely many unfixed EVEs present within species gene pools at a given time (known examples of unfixed EVEs include Israeli acute paralysis virus (IAPPV) insertions in honey bees (Apis mellifera), koala endogenous retrovirus (KoRV) in koala bears, and human herpesvirus 6 (HHV-6) and HERV-K HML-2 insertions in humans." https://lnkd.in/bBjWGE5 View in LinkedIn

FIXATION FOR SOME. "Viral infection of germ line cells (i.e. gametes, or cells of the early embryo) can lead to viral genes or genomes becoming integrated into chromosomes and inherited as host alleles. These insertions, which we refer to here as endogenous viral elements (EVEs), are usually eliminated from the host gene pool within a small number of generations. However, they can also increase in frequency, and some eventually reach fixation." https://lnkd.in/bBjWGE5 View in LinkedIn

ANCIENT RUINS. "One of these new studies...has uncovered some 80 examples of viral genetic data circulating in the genomes of vertebrate species for the past 40 million years." https://lnkd.in/bX9m4fJ View in LinkedIn