• Shawdow194@fedia.io
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    7 days ago

    In most other mammals, mutations in a protein called Mc1r lead to red hair color. But this has failed to explain orange color patterns in cats. “It’s been a genetic mystery, a conundrum,” Barsh tells Science’s Sara Reardon.

    Instead, the new studies point to a gene called Arhgap36, a protein on the X chromosome. It had never been in the lineup of potential candidates for the “orange gene,” so to speak, because it controls aspects of embryonic development.

    But the change wasn’t due to a dangerous mutation. Rather, there was a small portion of DNA missing, preventing the unusual amount of Arhgap36 from affecting anything aside from the melanocytes. So, cats with the orange variation “are not only healthy, but also cute,” Science writes.

    Interesting how we always talk about modifying or adding DNA but strange how removing some of it can end up with complicated results

    • ArcaneSlime@lemmy.dbzer0.com
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      7 days ago

      Arhgap36

      So you’re telling me my cat is airgapped? I’d believe it, she definitely isn’t receiving any intelligence updates.

    • The_v@lemmy.world
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      7 days ago

      The author was confused and that was written poorly. It is a mutation. A mutation is any change to the DNA sequence. Specifically it’s called a point mutation deletion. A point mutation is a small mutation of one nucleotide.

      The recipe for proteins on DNA is stored as a 3 nucleotide code. 3 nucleotides represent 1 amino acid (A protein is a chain of amino acids). A small deletion (1 or 2 nucleotidds) in the active coding sequence messes up the entire sequence.

      https://en.m.wikipedia.org/wiki/DNA_and_RNA_codon_tables

      • Shawdow194@fedia.io
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        7 days ago

        Yes! By defintion mutation is a change in DNA, but most people consider it more of a modification rather than the occasional just missing bit.

        We usually refer to missing DNAs as cancers since damaged and missing genetic data are the leading cause of unregulated cell division

        • The_v@lemmy.world
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          6 days ago

          Not quite, cancers are caused by any mutation that causes the regulatory proteins to stop being produced. Frameshift mutations are the most common cause. This are often caused by additions or deletions. However other mutations can deactivate the gene like a substitutionin the binding site for mRNA transcription.

          Mutations, like deletions can occur all across the genome. Since we have large amounts of non-coding DNA, these mutations usually have no effect.

      • The_v@lemmy.world
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        7 days ago

        It’s a recessive gene on the X chromosome.

        In females this means that it only expresses if both chromosome have the orange gene.

        Since males only have one X chromosome it always expresses if present.

        The orange males to female ratio in a population will average around 4:1.