Genetic Traits That Skip A Generation

There are none. That doesn't exist in science, sorry. Color deficiency doesn't "skip a generation", myopia doesn't "skip a generation", having twins doesn't "skip a generation"...there is no such thing. Sure, traits come & go (are expressed or not) and can even disappear altogether or reappear completely from a lineage...but there is no pattern for "skipping a generation". It's all genetic statistical probability. Just my medical/science PSA for the week!


  1. and just to add something else...identical twins are a statistical anomaly: the egg splits. That is not an "inheritable" trait. Having identical twins does not "run in families". It's literally a medical accident. The ability to have FRATERNAL TWINS (two separate eggs, both separately fertilized) *CAN* be inherited, because you can inherit (& pass on) the ability to MULTIPLE OVULATE. But *IDENTICAL* twins...that's just straight statistical probability: a certain number of eggs will split after being fertilized. No Genetics are involved. Nothing anyone (nor any gene) has any control over.

  2. Genetic Traits That Skip A Generation ... There are none. hmmm...

    Like many "old wife's tales" there is often a hint of truth in the statement. To say "there are none" as an absolute is, IMHO, equally misleading. [NOTE: Below is a simplified discussion to avoid a lot of scientific information]

    Let's say we have some plants that always have white flowers and we cross pollinate with the same species of plant but it always has blue flowers. Let's also say the gene for flower color is on a single allele with the white gene being recessive and the blue one dominant.

    The flowers that are always white must have only the white gene and the flowers that are blue only have the blue one. Lets call them cc for the white and CC for the blue, where c is the color gene.

    When we cross the white and blue flower plants we will get ALL blue plants in the first generation since they will all be cC. but in the second generation (crossing the new plants with each other) we get 50% cC, 25% CC and 25% cc. That means we get 25% of the plants with a white flower. The white appeared to skip a generation.

    Simplistic version, but it shows how something might skip a generation. This becomes much more true when the recessive gene is a life threatening one since the people with offspring with two recessive genes tend to die before they can reproduce.

    So technically you are correct. The gene's cannot skip a generation but the expression or manifestation of genes — traits — can skip generations under some circumstances.

    A good example of skipping a generation is Hemophilia if the mother is the carrier. Father's can't be carriers because they only have one X chromosome.

    Hope you find this useful!!


    1. "The white appeared to skip a generation"

      the key word here being "appeared"


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