3 ms·

The article says that 60% of the DNA is made up of repeating sequences, but then goes on to say that the reason American cockroaches thrive in cities is due to

The article says that 60% of the DNA is made up of repeating sequences, but then goes on to say that the reason American cockroaches thrive in cities is due to their 150 scent receptors and 500 taste receptors. I'm don't see the connection.

moh_maya 9y ago
Just based off the press release, and speculating a bit (note: this isn't implied in the article; this is my attempt to link up the long genome / repetitive elements and number of receptors) Repetitive DNA can allow for increased frequency of DNA recombination; depending on a host of factors (including the relative location of the repetitive elements and the receptor genes, etc) this may facilitate generation of new gene variants for the receptors, increasing the receptor diversity, while preserving / retaining the parent genes. Again, this is very simplistic speculative attempt to join the two dots.
gilleain 9y ago
From the abstract of the Nature article (open): https://www.nature.com/articles/s41467-018-03281-1 https://www.nature.com/articles/s41467-018-03281-1 There is : >In comparison with other insects, expansions of gene families in P. americana exist for most core gene families likely associated with environmental adaptation, such as chemoreception and detoxification. And from the body of the paper: >In contrast, the increase in gene number in cockroaches is mainly attributed to their expansion of universal genes in the 12 species we analyzed Specifically, for the American cockroach: >The gene sets of P. americana and B. germanica contained 13,555 and 10,107 multicopy universal genes, respectively, while the highest number of such genes in other insects was only 7708. So it seems like it is both that 60% is repetitive elements, and there are multiple copies of these 'universal' genes, where 'universal' means: > Universal groups represent common gene families across all species analyzed, but absence in at most one genome is tolerated;

moh_maya 9y ago

Just based off the press release, and speculating a bit (note: this isn't implied in the article; this is my attempt to link up the long genome / repetitive elements and number of receptors) Repetitive DNA can allow for increased frequency of DNA recombination; depending on a host of factors (including the relative location of the repetitive elements and the receptor genes, etc) this may facilitate generation of new gene variants for the receptors, increasing the receptor diversity, while preserving / retaining the parent genes. Again, this is very simplistic speculative attempt to join the two dots.

gilleain 9y ago

From the abstract of the Nature article (open): https://www.nature.com/articles/s41467-018-03281-1 https://www.nature.com/articles/s41467-018-03281-1 There is : >In comparison with other insects, expansions of gene families in P. americana exist for most core gene families likely associated with environmental adaptation, such as chemoreception and detoxification. And from the body of the paper: >In contrast, the increase in gene number in cockroaches is mainly attributed to their expansion of universal genes in the 12 species we analyzed Specifically, for the American cockroach: >The gene sets of P. americana and B. germanica contained 13,555 and 10,107 multicopy universal genes, respectively, while the highest number of such genes in other insects was only 7708. So it seems like it is both that 60% is repetitive elements, and there are multiple copies of these 'universal' genes, where 'universal' means: > Universal groups represent common gene families across all species analyzed, but absence in at most one genome is tolerated;