Snakes are a vital component of wildlife resources and are widely distributed across the globe. The many-banded krait Bungarus multicinctus is a highly venomous snake found across Southern Asia and central and southern China. Snakes are an ancient reptile group, and their genomes can provide important clues for understanding the evolutionary history of reptiles. Additionally, genomic resources play a crucial role in comprehending the evolution of all species. However, snake genomic resources are still scarce. Here, we present a highly contiguous genome of B. multicinctus with a size of 1.51 Gb. The genome contains a repeat content of 40.15%, with a total length exceeding 620 Mb. Additionally, we annotated a total of 24,869 functional genes. This research is of great significance for comprehending the evolution of B. multicinctus and provides genomic information on the genes involved in venom gland functions.

The mitochondrial genome (mitogenome or mtDNA), the extrachromosomal genome, is a multicopy circular DNA with high mutation rates due to replication and repair errors. A mitochondrion, cell, tissue, organ, or an individual body may hold multiple variants, both inherited and developed over a lifetime, which make up individual mitogene pools. This phenomenon is also called mtDNA heteroplasmy. MtDNA variants influence cellular and tissular functions and are consequently subjected to selection. Although it has long been recognized that only inheritable germline heteroplasmies have evolutionary significance, non-inheritable somatic heteroplasmies have been overlooked since they directly affect individual fitness and thus indirectly affect the fate of heritable germline variants. This review focuses on the characteristics, dynamics, and functions of mtDNA heteroplasmy and proposes the concept of individual mitogene pools to discuss individual genetic diversity from multiple angles. We provide a unique perspective on the relationship between individual genetic diversity and heritable genetic diversity and guide how the individual mitogene pool with novel genetic markers can be applied to ecological research.

Hair is a prominent physiological feature of many animals that can be easily and non-invasively sampled. However, most previous studies have focused on human hair, and animal hair has not been widely used as a DNA source in genetic and evolutionary studies. Analysing the DNA quality of animal hair is more challenging than that of human hair because it varies across different species and is influenced by different storage conditions. To address this gap in our knowledge, this study systematically evaluated the DNA quality of various animal hair samples. Our findings show that lightly medullated hairs, which are typical in carnivores, yield greater amounts of DNA and have better sequencing results than highly medullated hairs, which are typical in ungulate herbivores. Furthermore, the roots and middle hair were more productive than the upper hair parts. Tanning and storage time impair DNA yield and sequencing quality and increase nucleotide damage. Moreover, for certain historical specimens and field samples, genomic DNA was more successfully obtained from hair samples than from skin samples. This study provides data and theoretical support for improving the use of animal hair in genetic research.

The formation of animal breeds usually begins with a small subsample from their ancestral population. Deleterious mutations accumulate in the population under genetic drift, inbreeding, and artificial selection during the development and maintenance of traits desired by humans. White raccoon dogs are among the most popular breeds of farmed raccoon dogs, but white raccoon dogs are more susceptible to disease and have a lower reproductive ability. However, the accumulation of deleterious mutations in this white breed is largely unknown. By analyzing and comparing whole-genome sequencing data from 20 white raccoon dogs and 38 normal raccoon dogs, we detected an increased occurrence of loss-of-function (LoF) mutations in white raccoon dogs compared with normal raccoon dogs. With the finding of a significantly higher dosage of homozygous missense mutations in the white raccoon dog genome, we detected a greater fitness cost in white raccoon dogs. Although a much higher FROH level for ROH fragments longer than 1 Mb has been reported in white raccoon dogs, we did not detect a genetic signal of genetic purging in white raccoon dogs. This study provides valuable genomic resources and new insights into the accumulation of mutation loads in farmed raccoon dogs.

Snakes are a vital component of wildlife resources and are widely distributed across the globe. Bungarus multicinctus, a highly venomous snake, is found in central and southern China. B. multicinctus is a highly venomous snake and is distributed in central and southern China. Snakes are an ancient group of reptiles, and their genome resources can provide important clues for understanding the evolutionary history of reptiles. Meanwhile, genomic resources play a crucial role in comprehending the evolution of species. So far, the genomic resources of snakes are a rarity. In 2021, a snake sample was collected from Beiliu Longgukeng, Guangxi, which was identified as B. multicinctus through morphological identification. In this study, we present a highly contiguous genome of B. multicinctus with a size of 1.51 Gb. The genome contains a repeat content of 40.15%, with a total length exceeding 620 Mb. Additionally, we annotated a total of 24,869 functional genes. This research is of great significance for comprehending the evolution of B. multicinctus and provides a genomic basis for the genes involved in venom gland function.