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A lethal mutant gene in the Mexican axolotl

R R Humphrey

    The Journal of Heredity
    |November 1, 1977
    PubMed

    Insights

    A newly discovered gene, ph, in axolotls causes lighter coloration and significantly retarded limb development. This genetic mutation leads to reduced long bone length, high mortality rates, and renal abnormalities in affected larvae.

    Area of Science:

    • Developmental Biology
    • Genetics
    • Amphibian Research

    Background:

    • The axolotl (Ambystoma mexicanum) is a model organism for regeneration and developmental studies.
    • Genetic mutations can significantly impact axolotl development and physiology.
    • Understanding gene function is crucial for advancing regenerative medicine and developmental biology.

    Purpose of the Study:

    • To characterize a newly identified gene, designated ph, in axolotls.
    • To describe the phenotypic effects of the ph gene mutation on larval development.
    • To determine the inheritance pattern of the ph gene.

    Main Methods:

    • Observation of axolotl larvae from hatching.
    • Phenotypic analysis focusing on coloration and limb development.
    • Assessment of survival rates and post-mortem examination for abnormalities.

    Main Results:

    • Homozygosity for the ph gene results in lighter larval coloration.
    • Retarded forelimb development and subnormal limb length due to reduced long bone growth.
    • High mortality rates among affected larvae, with survivors exhibiting renal abnormalities, edema, ascites, or visceral adhesions.

    Conclusions:

    • The ph gene is a simple recessive gene with full penetrance.
    • This mutation severely impacts axolotl development, affecting skeletal growth and organ systems.
    • The ph gene provides a new tool for studying axolotl development and associated pathologies.

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