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2019 Stephen J O'Brien award

2019 Stephen J O'Brien award

The Stephen J. O'Brien Award for the best student paper published in AGA's Journal of Heredity is intended to honor Dr. O'Brien's many years of service as Chief Editor of the Journal. 

This year, the evaluation committee considered 10 articles in Volume 109 that were first-authored by students. The Stephen J. O’Brien Award went to William J. Gammerdinger for his article, Novel Sex Chromosomes in 3 Cichlid Fishes from Lake Tanganyika (William J. Gammerdinger, Matthew A. Conte, Benjamin A. Sandkam, Angelika Ziegelbecker, Stephan Koblmüller, and Thomas D. Kocher. JHered 2018. 109-5, pp 489-500).

The evaluation committee had the following comments on this top-ranked article:

"A very impressive analysis of next-generation genome sequencing to describe sex chromosome systems (XY and ZW) in Lake Tanganyika cichlids. The work reveals surprisingly rapid sex chromosome evolution, AND a novel color polymorphism locus. Based on an EECG award."

William will receive a $2,000 prize, a certificate, and up to $2,000 toward expenses to attend the 2019 AGA President's Symposium.

The article is freely available to read and download.

Gammerdinger et al. 2018 Description and Importance

The genetic polymorphisms responsible for sex determination drastically alter the nearby genomic landscape. Chromosomal rearrangements can lead to the accumulation of mutations in neighboring genes. The heteromorphic Y-chromosome of many eutherian mammals can stand as an example of the long-term consequences of these processes. With the advent of next-generation sequencing, we can now characterize many young, homomorphic sex chromosomes to study the rates and patterns of sex chromosome divergence.

African cichlids are diverse in numerous traits, including a wide variety of sex chromosome systems. This study analyzed three species of African cichlids endemic to Lake Tanganyika and detected at least two novel sex chromosome systems. The sex chromosome system of the third species may be convergent with a system observed in Lake Malawi. Lastly, this study identified candidate SNPs in one of these species that may be responsible for a tail color polymorphism.

Earlier research on the sex chromosome systems of Lake Tanganyika cichlids has been sparse. This work helps illuminate the rich diversity of sex chromosome systems within these fishes and highlights the rapid decay and frequent transitions between sex chromosome systems within this group. Additional work on these species will enhance our understanding of the early stages of sex chromosome evolution and also add to our understanding of how transitions between sex chromosome systems occur.

William 'Will' Gammerdinger Biography

Will Gammerdinger is an evolutionary geneticist who recently finished his PhD at the University of Maryland in the laboratory of Dr. Thomas Kocher. His PhD used whole genome resequencing to characterize a diverse array of sex chromosome systems in African cichlids. His work has revealed widespread differentiation among young sex chromosome pairs and numerous transitions between sex chromosome systems among closely related species. He is currently a post-doctoral researcher at IST Austria studying the role that whole genome duplications play in resolving sexual conflict. Broadly, his research interests include understanding the dynamics of sex chromosome transitions, elucidating the interactions between genes in the sex determination network and investigating potential mechanisms for resolving sexual conflict.

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Variable Signatures of Selection Despite Conserved Recombination Landscapes Early in Speciation
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The Editorial Board announces a new article category, Genome Resources, for manuscripts that describe genome assembly resources of practical value to the broader scientific community


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