(1927) – Muller and his Microscope
Did you know that the very first theory of the telomere got it right? Lucky guess? No. Just sound deductive reasoning.
Twenty-six years before Watson and Crick described DNA’s double helix, Herman Muller, a scientist from Harlem and the Bronx, was irradiating fruit flies at Woods Hole to produce mutants with deletions and inversions involving the ends of chromosomes. High energy rays produce DNA breaks, which is why UV exposure gives us skin cancer.
Because he never created deletions or inversions that affected the natural tips of the chromosomes, he concluded that:
‘‘. . . the terminal gene must have a special function, that of sealing the end of the chromosome, so to speak, and that for some reason a chromosome cannot persist indefinitely without having its ends thus sealed.’’
Muller coined the term “telomere” for the tips of chromosomes from Greek: “telo” for ‘‘end’’ and “mere” for “body.” For his work in creating genetic mutations with X-rays, he takes home the Nobel Prize in 1946.
(1953) – Watson and Crick explain the double helix
Watson and Crick explained the structure of the double helix of chromosomes. They explained that DNA is a code paired to an opposite strand. For this, they won the Nobel Prize in 1962.
(1961) – The Hayflick Limit
Leonard Hayflick discovered that cells are not immortal and can only divide about 50 times before becoming non-viable (the so-called “Hayflick Limit” for telomerase-insufficient cells.)
He theorized that there must be a way the cells remember how ‘old’ they are and pass it along. We now know that is primarily from the length of the cell line’s telomeres.
Okazaki explained that since it is impossible to assemble a lagging strand of DNA in the 3′ to 5′ direction, it has to be written in small 5′ to 3′ segments, begun with primers, and joined together before replacing the primer RNA with regular DNA.
(1973) – Olovnikov’s telomerase theory
Alexey Olovnikov, a Russian biologist, theorized that there must be a mechanism to create actively generate more length in the telomeres. His reasoning was that since DNA always shortens with replication, without elongation, we could be unsustainable.
(1984) – Telomerase discovered
Blackburn, Sjostak & Greider find Olovnikov’s theorized mechanism in the form of the enzyme, telomerase.
For this discovery, the trio won the Nobel Prize in Medicine in 2009.
(2004) – Telomerase activator TA-65
Geron patented the extraction of TA-65, a small molecule activator of the body’s normal telomerase healing mechanism.
People begin taking this via TA Sciences in 2005.
(2009) – Dr. Ed Park’s Stem Cell Theory of Aging
Knowledgeable people may consider my stem cell theory of aging to be a statement of the obvious, as do I. But a greater number believe that aging is more complicated than just telomere erosion in stem cells and favor other theories. To read their theories and compare them with mine, go to https://www.rechargebiomedical.com/aging.html
Of course, theories are like opinions…everyone has one. I very much welcome your emails telling me why my theory has holes or is just plain wrong.
3 thoughts on “Genetics 101: The least you need to know”
this is nice information of events in molecular biology.
The link to read their theories and compare them with yours is a broken link. 😖 My question is, how do you seal off the end of a chromosome… You would have to do that at a certain age right?
The chromosomes are active and are never sealed off. Because of DNA replication mechanics, you just can’t copy to the ends so there is always loss. Natures solution is to actively lengthen the telomeres in stem cells.