amphitoky's comments

amphitoky | 2 years ago | on: Ask HN: What are your 'mental hacks' to remember small tasks?

Not entirely related to little tasks from meetings, but when I need to remember something eg. the next morning but I'm already in bed and dont want to get up to write it down etc, I find that a quick way to remind myself is to take something nearby, for example the book on my nightstand or just a crumpled tissue or two, and throw it on the ground where I'll see/stumble over it the next morning and think "why is this here" and then remember.

amphitoky | 3 years ago | on: Butterfly wing patterns emerge from ancient ‘junk’ DNA

people like to forget DNA has a 3D structure. A lot of the DNA that doesnt encode proteins might be involved, for example, in the association of 3D topological domains or conformational switches that impact chromatin accessibility. Interesting also is when sufficient factors bind to a local region of DNA to change the local chemistry and initiate phase separated domains where regulatory factors might preferrentially bind and thus drive the transcription of the few coding regions, and that's pretty cool too. Just to add some context to your bits-analogy.

amphitoky | 6 years ago | on: Scientists discover virus with no recognizable genes

that's not just true for viruses, it's true for pretty much anything. we've barely scraped the surface in terms of sequencing microbes, fungi, plants, birds, fish, ..., not to even consider variation at the population (or god forbid, somatic cell) level.

amphitoky | 6 years ago | on: Elephants Rarely Get Cancer, Now We Know Why (2015)

as others have said, genetic therapies for these kinds of transmissible cancers are not so effective since the cells have already acquired the cancer phenotype. The usual regulatory mechanisms which prevent unchecked proliferation occur in each individual cell, and have already been circumvented by the time cells become cancerous.

I thought I would add that what makes the tasmanian case interesting is that though the body is generally pretty good about detecting and removing foreign cells (including viruses and bacteria), somehow these contagious cancers elude this detection and are allowed to proliferate [1]. It is likely that if the tasmanian devil's immune system were able to detect the intruder cancer cells as coming from another individual, it would eradicate them with ruthless efficiency. Why these cells are able to skirt the host immune system though is a different question.

[1] https://www.ncbi.nlm.nih.gov/pubmed/28695294

amphitoky | 9 years ago | on: In Newly Created Life-Form, a Major Mystery

no, it is a consensus sequence determined by sequencing the genomes of several individuals. i do not know how many individuals were sequenced for hg38, but hg37 was derived from 13 individuals according to [1].

genomic regions with higher variability between individuals are annotated separately and are not represented in the main chromosomal sequence, but can be aligned to it as such.

[1] https://en.wikipedia.org/wiki/Reference_genome

amphitoky | 9 years ago | on: In Newly Created Life-Form, a Major Mystery

the cellular genome size of RGD3.0, the organism with a 473 genome, is 531kbp according to the paper. this means that the genome encompasses ~531,000 nucleotides (base-pairs). for reference, the human genome encompasses approximately 3.3-billion base-pairs.

you can download the human genome from here http://hgdownload.soe.ucsc.edu/goldenPath/hg38/bigZips/hg38.... (it is recommended to use ftp, see: http://hgdownload.soe.ucsc.edu/goldenPath/hg38/bigZips/). it is an ~800mb download.

if it takes 800 mb to store 3.3 billion bases, i would assume it takes (531k / 3.3b) * 800 mb = 0.141 mb to store this genome.

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