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bioRxiv · 10.1101/2025.11.27.690999

Chromosome-Level Genome Assembly of Southern Africa Mozambique Tilapia (Oreochromis mossambicus) using PacBio HiFi and Omni-C sequencing

TSHILATE, T. S.·Nesengani, L. T.·Mdyogolo, S.·Smith, R. M.·Molotsi, A. H.·Masebe, T.·Mapholi, N.
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Abstract

The Mozambique tilapia (Oreochromis mossambicus) is a species of significant ecological and economic importance in Southern Africa. However, urbanization and water management challenges have led to the species being classified as threatened by the International Union for Conservation of Nature. Despite its widespread distribution and significance as a key food source, the genetic architecture of Southern African O. mossambicus remains inadequately characterized. This gap in knowledge hinders efforts to conserve and manage the species effectively. This study presents a high-quality chromosome-level genome assembly for a South African O. mossambicus assembled using both PacBio HiFi and Dovetail Omni-C sequencing. The 1.09 Gb assembly is highly contiguous, with 99.4% of sequences anchored into 22 chromosomes and a BUSCO completeness of 99.5%. We annotated 27,544 protein-coding genes. This genome provides an essential resource for preserving native biodiversity and enabling genomic selection for traits like disease resistance and growth performance within the South African aquaculture context.

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TSHILATE, T. S., Nesengani, L. T., Mdyogolo, S., Smith, R. M., Molotsi, A. H., Masebe, T., Mapholi, N.. 2025-11-29. Chromosome-Level Genome Assembly of Southern Africa Mozambique Tilapia (Oreochromis mossambicus) using PacBio HiFi and Omni-C sequencing. https://doi.org/10.1101/2025.11.27.690999

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