Question about DNA gene mutations?!?

Question

If substitution in a DNA sequence occurred in a reproductive cell of a fish that was later fertilized to become an offspring, how might it impact the organism?

Answer 1

It's not nearly as vague and hypothetical as the other answers have said. You can see from the mRNA sequence that the mutation affects the second codon. The first is AUG, which is the start codon. The original gene's second codon would have been UGG (complimentary to ACC), and in the mutant it's UAG instead. If you look up the genetic code, you find that UGG codes for tryptophan, while UAG is a stop codon. So instead of coding for a protein, the mutant sequence codes for one amino acid and then stops. The fish doesn't make the protein at all.



Now, the first answer was correct in that we can't predict what affect this might have in the offspring. It could be that the fish only needs one copy of the gene, in which case it'll be fine. Or perhaps this gene isn't very important, and losing it won't have any real effect. Or, it could be that the loss of this allele will be instantly deadly. Or anything in between. All we can say is that this allele is completely nonfunctional.

Answer 2

Although the effects of mutation can vary greatly, the nature of effect can still be considered by probability.

Since this mutation is specifically mentioned to be a substitution, in most cases this causes minimal effects in the organism with the mutation. Most substitution, especially if at the 3rd or even the 2nd position (as is given in this example) lead to a synonymous mutation, that is, there is no change in the amino acid they encode. However, it could also lead to having a different amino acid in that position. This can have effects ranging from very mild to very severe depending on where this substitution has occurred and what kind of amino acid substitution has occurred.

Answer 3

Genetic encoding can be converted, mutated and have genes being delivered to it. As an instance, the Pinot Noir (wine grape) has about 30,000 genes in its DNA. That is greater than the human genome, which includes some 20,000 to 25,000 genes. That might be due to the consistent changes humans made to the grape to get more and more flavour. This of course takes some time but with humans forcing alternate it was once manner faster than mud to dinosaurs (three billions years) DNA collects mutation always. That's how scientists can collect knowledge on how the species transformed by evaluating DNA sequences. Mutation can imply additional genes appearing by way of... Ahem... Mutation, that is a breakdown within the order chain. That type of factor appears in every living species in the world. Identical to folks with further chromosomes. There's a conception that earlier than DNA lifestyles used RNA, to which DNA was slowly 'grafted' and took over (that's an extraordinarily rough rationalization, i know). That suggests an extended RNA/DNA chain as DNA was added to it. "The ENCODE consortium’s primary findings include the discovery that the majority of human DNA is transcribed into RNA and that these transcripts generally overlap one an extra. This large pattern of transcription challenges the lengthy-standing view that the human genome includes a small set of discrete genes, together with a tremendous amount of “junk” DNA that isn't biologically energetic. The brand new data point out that the genome contains little unused sequences; genes are simply one in all many varieties of DNA sequences that have a practical affect. The consortium identified many earlier unrecognized start websites for transcription and regulatory sequences that opposite to normal views are located now not best upstream but in addition downstream of transcription web sites. Other surprises in the ENCODE information have principal implications for our figuring out of the evolution of genomes. Unless just lately, researchers had notion that most DNA sequences with most important organic operate could be limited by using evolution making them prone to be conserved as species evolve. But about 1/2 of the realistic elements within the human genome do not appear to have been limited in the course of evolution, suggesting that many species’ genomes contain a pool of functional elements that furnish no distinct advantages in phrases of survival or copy."

Answer 4

It is completely theoretical. Who knows? Probably nothing, since most mutations are usually recessive. Also it depends what type of mutation. There are mutations that makes the organism not-viable, there are mutations that cause absolutely no effect on the organisms DNA.

Answer 5

That's a good question and I hope you get some reasonable answers