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IntroductionModern understanding of the concept of genetic diversity must include the study of both nuclear and organellar DNA, which differ greatly in terms of their structure, organization, gene content and distribution. This study comprises an analysis of the genetic diversity of the smut fungusSporisorium reilianumf. sp.zeaefrom a mitochondrial perspective. MethodsWhole-genome sequencing data was generated from biological samples ofS. reilianumcollected from different geographical regions. Multiple sequence alignment and gene synteny analysis were performed to further characterize genetic diversity in the context of mitogenomic polymorphisms. ResultsMitochondria of strains collected in China contained unique sequences. The largest unique sequence stretch encompassed a portion ofcox1, a mitochondrial gene encoding one of the subunits that make up complex IV of the mitochondrial electron transport chain. This unique sequence had high percent identity to the mitogenome of the related speciesSporisorium scitamineumandUstilago bromivora. DiscussionThe results of this study hint at potential horizontal gene transfer or mitochondrial genome recombination events during the evolutionary history of basidiomycetes. Additionally, the distinct polymorphic region detected in the Chinese mitogenome provides the ideal foundation to develop a diagnostic method to discern between mitotypes and enhance knowledge on the genetic diversity of this organism.
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This content will become publicly available on June 25, 2026
Assessment of the genetic diversity of Atlantic bottlenose dolphin (Tursiops truncatus) strandings in the Mississippi Sound (USA)
The common bottlenose dolphin (Tursiops truncatus) is a key marine mammal species in the Gulf of Mexico, playing an essential role as a top predator. This study investigates the genetic diversity and population structure of bottlenose dolphins stranded in the Mississippi Sound from 2010 to 2021. Tissue samples (muscle, liver, lung, kidney, and brain) were collected from 511 stranded dolphins, and mitochondrial DNAs (mtDNA) were extracted for analysis. A total of 417 samples were successfully amplified and sequenced using high throughput sequencing, yielding 386 complete mitogenomes. Genetic diversity metrics, such as nucleotide and haplotype diversity, were calculated, and population structure was inferred for both mitochondrial control region (mtCR) and whole mitogenome sequences. Using the whole mitogenome, the study identified four genetically distinct populations within the Mississippi Sound, demonstrating regional variation in dolphin populations. Notably, two stranded individuals likely originated from populations outside the sampled area. The use of whole mitogenomes allowed for improved resolution of genetic diversity and population differentiation compared to previous studies using partial mtDNA sequences. These findings enhance our understanding of bottlenose dolphin population structure in the region and underscore the value of stranded animals for population genetic studies.
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- Award ID(s):
- 2209115
- PAR ID:
- 10612483
- Publisher / Repository:
- PLOS
- Date Published:
- Journal Name:
- PLOS One
- Volume:
- 20
- Issue:
- 6
- ISSN:
- 1932-6203
- Page Range / eLocation ID:
- e0314249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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