A rapid decline in Bacterial genome size after intense adaptation
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6986707/
Recombination and gene loss occur simultaneously during bacterial horizontal gene transfer
Excerpt: "Bacteria can acquire new genes by incorporating environmental DNA into their genomes, yet genome sizes stay relatively constant. In nature, gene acquisition is a rare event so it is difficult to observe. However, the Caulobacter crescentus CB2A genome contains 114 insertions of genetic material from the closely related NA1000 strain, providing a unique opportunity to analyze the horizontal transfer of genetic material. Analyses of these insertions led to a new model that involves preferential recombination at non-homologous regions that are flanked by regions of homology and does not involve any mutational processes. The net result is the replacement of segments of the recipient genome instead of the simple addition of genetic material during horizontal gene transfer. Analyses of the genomes of closely related strains of other bacterial and archaea genera, suggested that horizontal gene transfer occurs preferentially in non-homologous regions in these organisms as well. Thus, it appears to be a general phenomenon that prokaryotic horizontal gene transfer occurs preferentially at sites where the incoming DNA contains a non-homologous region that is flanked by regions of homology. Therefore, gene replacement is a common phenomenon during horizontal gene transfer.
My comment: There seems to be a genus-specific maximum limit for genome size in bacteria. In some cases, bacteria are able to partially restore their genome contents by plasmid transfer.
Horizontal gene transfer in the human genome has never been observed.
A rapid decline in Bacterial genome size doesn't support evolution
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4988878/
Excerpt: "After 50,000 generations, average genome length declined by 63 kbp (~1.4%) relative to the ancestor"
My comment: 'Horizontal Gene Transfer' has been one of the favorite 'proofs of evolution' for evolution believers. Now this outdated theory has been debunked. Instead, we can observe rapid loss of biological information during adaptive processes within all kinds of organisms. Lenski's famous LTEE proves this fact; after 50,000 generations of bacteria (~25 years) there's a significant loss of information in bacterial genomes. Today, after ~90,000 generations the loss of information is very likely more than 3% because after mutations hit DNA repair mechanisms, the effect of hypermutability arises very rapidly resulting in the extinction of bacterial strains. Evolution never happened.
