Genetic Diversity of Devil's Hole Pupfish Affected by Harsh and Isolated Conditions

The Devil's Hole pupfish, a rare desert pupfish from the American Southwest, had its genome sequenced for the first time.

The 8 Devils Hole pupfish whose genomes were analyzed had the most similar DNA regions (58% of the genomes), among the most inbred vertebrates ever discovered.

Contrary to expectations, five of the 15 gene deletions entailed adaptation to hypoxia, or low oxygen levels, which have been typical of the pupfish's environment.

The most inbred creature known is the endangered Devils Hole pupfish

(Photo : ROBYN BECK/AFP via Getty Images)

Biologists from the University of California, Berkeley report the first complete genome sequences of eight different pupfish species from the American Southwest, totaling 30 individuals, including eight Devils Hole pupfish, in a paper that was published this week in the journal Proceedings of the Royal Society B. Surprisingly, the Devils Hole pupfish has undergone such intense inbreeding that, on average, 58% of the genomes of such eight individuals are identical, as per ScienceDaily.

The Devil's Hole pupfish exhibit an amount of inbreeding comparable to what would occur if four to five generations of siblings interbred, according to graduate student David Tian, the study's lead author.

As a result, dangerous mutations are more likely to be fixed or burned in rather than eliminated, potentially driving a species to extinction through a mutational meltdown.

Although populations of Devil's Hole pupfish in the wild and captivity, or refuge populations, are currently thriving, the species' low genetic diversity may cause problems if climate change and human influences increase.

The new genome sequences will aid researchers and conservationists in evaluating the condition of native pupfish populations and maybe intervening in refuge populations to boost the genetic variety of these species, specifically the Devil's Hole pupfish.

The new genome sequences will aid researchers and conservationists in evaluating the condition of native pupfish populations and maybe intervening in refuge populations to boost the genetic variety of these species, specifically the Devil's Hole pupfish.

Read More: Devils Hole Pupfish: Get to Know the Rarest Fish in the World

Rate of genetic diversity loss used to identify endangered animals

Conservationists can predict the number of generations left before a population hits a threshold of minimal genetic variety using a statistical method created by Janna Willoughby and Andrew DeWoody, then-doctoral wildlife genetics students, at per Purdue University.

According to Willoughby, a population's long-term survival depends heavily on its genetic diversity. The method they created identifies populations with insufficient genetic variety, which will prevent the population from surviving over time.

They discovered that this approach greatly outperforms existing techniques for identifying species that require conservation efforts.

With our current methods, Willoughby warned, we might miss populations with low genetic diversity unless they have experienced a sharp decline in size.

So that a species doesn't become extinct just because we didn't notice it, genetic diversity should be taken into account when assessing conservation priorities.

Effects of inbreeding animals

Animals that have been inbred are less productive and much more likely to develop hereditary diseases, as per LIC.

Recessive gene-related illnesses are also more likely to develop in inbred individuals. Calf deformities, miscarriages, and stillbirths can result from these conditions.

For an animal to have the condition, two copies of the recessive gene must be present. Each parent gives them one copy of the gene.

A copy of the same recessive gene is more likely to be present in closely related animals. Due to this, there is a higher chance that both of them will transfer the gene to their progeny.

Related Article: Nevada's Endangered Pupfish Threatened by Climate Change