Detection of sex chromosomes in Tephritid pests using R-CQ and KAMY, two computational methods to support generic pest management applications

Abstract

The detection and characterization of sex chromosome sequences is particularly important for major pest families, like the Tephritidae, whereas alternative pest management approaches, mainly involving male-only release programs, rely on the ability to target and manipulate sex-specific genomic regions, particularly those of the Y chromosome. However, resolving and detecting X and Y chromosome sequences at the chromosome level requires careful consideration of algorithmic outputs, especially in species where extensive sex chromosome markers are not available. Here, we present R-CQ and KAMY, two computational methods developed for the detection of sex chromosome-linked sequences through sex-specific short-read DNA sequencing datasets. We evaluate their performance on newly generated chromosome-level assemblies of four important Tephritid pest species: Ceratitis capitata, Bactrocera dorsalis, Bactrocera zonata, and Anastrepha ludens. By combining algorithmic predictions with a manual curation process, we assess the strengths and limitations of each method and provide a robust dataset of curated X- and Y-linked sequences. Overall, our results establish a framework for studying poorly characterized sex chromosome lineages and identifying sex-specific genomic regions, supporting the broader development of sex chromosome-based pest managements systems.

Keywords

computational biology / KAMY / pest management / R-CQ / sex chromosomes / Y chromosome

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2025 The Author(s). Insect Science published by John Wiley & Sons Australia, Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.