this post was submitted on 07 Feb 2024
117 points (81.3% liked)

science

14697 readers
90 users here now

just science related topics. please contribute

note: clickbait sources/headlines aren't liked generally. I've posted crap sources and later deleted or edit to improve after complaints. whoops, sry

Rule 1) Be kind.

lemmy.world rules: https://mastodon.world/about

I don't screen everything, lrn2scroll

founded 1 year ago
MODERATORS
 

Review of 2023 book: How Life Works: A User’s Guide to the New Biology Philip Ball. ISBN9781529095999

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 4 points 9 months ago (13 children)

I'm not an expert on the subject. I can only repeat what Venter said: "the only junk DNA is in my colleagues brains". He claims that all DNA has function and that it should not be referred to as junk just because we don't know the function yet.

He talks about at intervals in this interview.

[–] [email protected] 1 points 9 months ago (10 children)

If there is a random mutation that is neither advantageous nor disadvantageous, wouldn't that be junk DNA?

Are we going to say we need to see how every descendant of the creature fares before we can decide whether it was junk DNA or not?

[–] [email protected] 2 points 9 months ago (4 children)

I don't know too much about the subject, but maybe this almost 30 year old article can help. There's more specific examples in the article, but this quote captures the direction:

"I don't believe in junk DNA," said Dr. Walter Gilbert of Harvard University, a pre-eminent theoretician of the human genome. "I've long believed that the attitude that all information is contained in the coding regions is very shortsighted, reflecting a protein chemist's bias of looking at DNA." Coding regions may make the proteins that are dear to a chemist's heart; but true biologists, he added, know that much of the exquisite control over these proteins is held offstage, nested within the noncoding junk.

[–] [email protected] -2 points 9 months ago (1 children)

@TempermentalAnomaly @morphballganon
Junk dna was junk science from the start for ignoring that evolution often eliminates or reduces useless things, like eyes in cave fish, so there’s little likelihood that there’s useless parts of the genome.

[–] [email protected] 4 points 9 months ago

But it doesn't do that instantly and it does it for good reason, eyes and the sections of the brain using them require energy and are vulnerable to infection so in situations where they don't provide an advantage they increase the likelihood of death before breeding thus giving any offspring born with less energy devoted to eyes has a small advantage which over s very long time results in them being selected away.

So unless the creatures reach a perfect form for their environment then they'll always be in the process of changing and have some of the old junk in there. Also if the formerly useful part doesn't make any real difference to survivability there's no force driving it to be selected away from, it might eventually be removed by lots of pure chance events but that's going to take a huge amount of generations meaning the middle time where there's junk not yet removed us going to be very long

load more comments (2 replies)
load more comments (7 replies)
load more comments (9 replies)