In Mendelian genetics
, it is accepted that autosomal dominant syndromes only reguire one gene abnormality.
Early in the 20th century, a vicious new strain of eugenics emerged in America, based on the new science of Mendelian genetics
. In the context of Progressive-era reformist zeal, belief in a strong government, and faith in science to solve social problems, eugenics became the basis of coercive social policy and even law.
(Carrier in this sense is not strictly identical to the meaning in Mendelian genetics
, thus the quotation marks.)
Stalin rejected Mendelian genetics
and even Darwin's theory of evolution, in favor of the bogus theories of Trofim Lysenko, the Soviet biologist who believed that human traits were acquired, not inherited.
Such speculation picks up steam with the biological discoveries of the twentieth century, from the rediscovery of Mendelian genetics
, through Watson and Crick's determination of the double helix structure of DNA, and onward through recombinant DNA technologies and discoveries concerning gene regulation, all the way up to the Human Genome Project at the end of the twentieth century.
These variations in the expression of both the rolling and folding traits as dominant or as recessive show that the inheritance of each of these traits is more than simple Mendelian genetics
. The dominance demonstrated in tongue folding or tongue rolling cannot be as described as a simple one gene, two allele genetic character with the rolling allele completely dominant over non-rolling and the folding allele completely dominant over non-folding.
For example, in 1910, Mendelian genetics
appeared to present a complete explanation of heredity and was used to justify an appalling program of segregation, marriage restriction, and sexual sterilization.
Today, science limits Mendelian genetics
to the explanation of simple dominant-recessive schemes, acknowledging that genetic variation within a group may exceed variation between groups.
The disease phenotype is inherited with Mendelian genetics
, so that it occurs much less often than the genes - it only occurs when a child inherits a mutant gene from each parent.
He uses a non-reductionist approach, and asks whether a few aspects of older developmental and Lamarkian biology are worth remembering, not as alternatives to Mendelian genetics
but as gropings toward an understanding of non-genetic factors interacting with genetic ones.
Inheritance patterns for magical talent, as Stockslager demonstrated, depart intriguingly from Mendelian genetics
in certain ways.
, which back then was not fully accepted by the scientific community, would exert a great influence on Vavilov's ideas.