Category: Uncategorized

GREGOR MENDEL. "There is no greater legend in the history of science than that of the experiments of Gregor Mendel. Three moments in this legend are extraordinary: first, how in the 1860s, Mendel discovered the laws governing the inheritance of individual characters; second, how the scientific world failed to recognise the monumental importance of these findings during his life-time; and third, the remarkable ‘rediscovery’ in 1900 of what later came to be called Mendelism." https://lnkd.in/dKsN9QF View in LinkedIn

SEVEN CHARACTERISTICS. "Mendel started his experiments by carefully selecting seven qualitative characters in peas (Pisum sativum L.) in 1856, and his results were published in 1866." Astonishingly this is the basis of our knowledge of predictable Mendelian inheritance. https://lnkd.in/d42Fwde View in LinkedIn

GREGOR MENDEL's work on heredity has endured 156 years, despite his Christian views and disbelief in Darwin. He was also a gentleman scientist, like many of the day, working outside traditional science funding institutions. Despite the fact that nothing was known at the time about DNA, chromosomes, genes or meiosis, his rigorous observations have largely stood the test of time. Inconsistencies of his laws have been identified and explained by modern research. View in LinkedIn

CORE. "The most important principle of Mendel's Law of Independent Assortment is that the emergence of one trait will not affect the emergence of another. For example, a pea plant's inheritance of the ability to produce purple flowers instead of white ones does not make it more likely that it would also inherit the ability to produce yellow peas in contrast to green ones." https://lnkd.in/dfsvaCA View in LinkedIn

THE EXCEPTIONS to Mendelian inheritance are perhaps as interesting as the many mechanisms that are upheld by Mendelian laws. These exceptions once again illustrate that nature is the master of innovation, and the subtlety and daring of the alternative mechanisms could barely be imagined a priori. View in LinkedIn

PART FOUR. "The fourth law states that, "The two genes for each character segregate during gamete production." This is the last part of Mendel's generalization. This references meiosis when the chromosome count is changed from the diploid number to the haploid number. The genes are sorted into separate gametes, ensuring variation." https://lnkd.in/dfsvaCA View in LinkedIn

TOO GOOD? "The closeness of Mendel’s experimental observations to those predicted by his theories have led to numerous articles and ongoing debate about whether the data could have been obtained in the published form without some modification. There have been many plausible arguments made for and against this view by a range of eminent statisticians and geneticists." https://lnkd.in/d42Fwde View in LinkedIn

FOUNDATION AND LEGACY. "It would be possible to teach a well-balanced and modern genetics course based almost entirely on the use and understandings derived from Mendel’s seven characters." https://lnkd.in/d42Fwde View in LinkedIn

ISSUE OF LINKAGE. "Certainly Mendel would be surprised by the phenomenon of linkage. It should be noted that during the 1950s and 1960s it became common for textbooks to indicate that Mendel’s seven characters were each located on separate chromosomes. In 1970 Ian Murfet pointed out this mistake, and it was subsequently corrected by a brief article in Nature by Stig Blixt." https://lnkd.in/d42Fwde View in LinkedIn

NEW ADDITIONS. "However, he would probably have also been surprised by some of the findings, for example, the finding that there can be intragenic recombination and other “large-scale” disruption of the inheritance units, which he envisaged to be transmitted intact from parent to offspring. However, such discoveries have added to and have refined the Mendelian model, rather than undermined it." https://lnkd.in/d42Fwde View in LinkedIn