Evidence map›Paper›PMID 42298410›Full record

ArticleBMC genomics2026

Moderate-high heritability and QTL associated with Manila clam Ruditapes philippinarum resistance to the parasite Perkinsus olseni.

I M Sambade, A Cao, D Costas, J A de Santiago, M Ortega-Iñarrea, M Hermida, B G Pardo, A Caballero, M Gallo, A Villalba and 1 more

Abstract read
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Article in BMC genomics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

11 authors.

I M Sambade *Department of Zoology, Genetics and Physical Anthropology, Faculty of Veterinary, Campus Terra, Universidade de Santiago de Compostela, Lugo, 27002, Spain.
A Cao *Centro de Investigacións Mariñas (CIMA), Consellería do Mar, Xunta de Galicia, Pontevedra, Vilanova de Arousa, 36611, Spain.
D CostasCentro de Investigación Mariña, Universidade de Vigo, Vigo, 36310, Spain.
J A de SantiagoCentro de Investigacións Mariñas (CIMA), Consellería do Mar, Xunta de Galicia, Pontevedra, Vilanova de Arousa, 36611, Spain.
M Ortega-IñarreaCentro de Investigacións Mariñas (CIMA), Consellería do Mar, Xunta de Galicia, Pontevedra, Vilanova de Arousa, 36611, Spain.
M HermidaDepartment of Zoology, Genetics and Physical Anthropology, Faculty of Veterinary, Campus Terra, Universidade de Santiago de Compostela, Lugo, 27002, Spain.
B G PardoDepartment of Zoology, Genetics and Physical Anthropology, Faculty of Veterinary, Campus Terra, Universidade de Santiago de Compostela, Lugo, 27002, Spain.
A CaballeroCentro de Investigación Mariña, Universidade de Vigo, Vigo, 36310, Spain.
M GalloDepartment of Zoology, Genetics and Physical Anthropology, Biological Research Center (CIBUS), Universidade de Santiago de Compostela, Santiago de Compostela, 15706, Spain.
A VillalbaCentro de Investigacións Mariñas (CIMA), Consellería do Mar, Xunta de Galicia, Pontevedra, Vilanova de Arousa, 36611, Spain. villalba.garcia.antonio@gmail.com.
P MartínezDepartment of Zoology, Genetics and Physical Anthropology, Faculty of Veterinary, Campus Terra, Universidade de Santiago de Compostela, Lugo, 27002, Spain. paulino.martinez@usc.es.

Funding

Programa Ciencias Mariñas de Galicia PRTR-C17.I1Xunta de Galicia ED431C 2022/33
6 · The paper itself

Abstract

backgroundThe Manila clam (Ruditapes philippinarum) is one of the most valuable bivalves in global aquaculture, but its production is increasingly threatened by Perkinsus olseni, a protozoan parasite responsible for severe mortality events on shellfish beds. Understanding the genetic basis of resistance to this pathogen is essential for developing sustainable breeding strategies and reducing economic losses.

resultsWe conducted a genome-wide association study (GWAS) on 606 Manila clam offspring from 32 full-sib families to investigate the heritability and genomic architecture of resistance to P. olseni. Following quality control and exclusion of the 42 smallest individuals potentially affected by size-related exposure bias, 564 offspring were retained for the final GWAS analyses. Genomic screening was performed with a newly developed multispecies SNP array comprising 49,392 SNPs for R. philippinarum. Experimental challenges were carried out in two tanks (challenged and control), each containing 1,500 offspring, and parasite load was quantified by qPCR using control Ct values as a non-infected reference. A substantial proportion of phenotypic variation in parasite load was explained by additive genetic effects, with heritability estimated at h² = 0.45 ± 0.09 using the full dataset and increasing to h² = 0.53 ± 0.08 after filtering. Several genome-wide significant quantitative trait loci (QTL) were identified across seven chromosomes, supporting a polygenic basis for resistance. Notably, one QTL on chromosome 18 also showed a highly significant association within one of the largest families. Patterns of linkage disequilibrium (LD) revealed rapid decay across most chromosomes, typical of marine bivalves, except for three chromosomes showing extended LD patterns compatible with putative structural polymorphisms, including possible inversions.

conclusionsThese results demonstrate a substantial additive genetic component underlying resistance to P. olseni in Manila clam and highlight chromosome 18 as an important genomic region associated with parasite burden. Overall, our findings support the future integration of genomic tools into selective breeding programmes aimed at improving disease resilience and promoting the long-term sustainability of Manila clam aquaculture under increasing environmental and pathogen pressures.

Indexed as

AlveolataBivalviaHost-Parasite InteractionsAnimalsAquacultureDisease ResistanceFemaleGenome-Wide Association StudyMaleParasite LoadPolymorphism, Single NucleotideQuantitative Trait LociIndoor challengeLinkage disequilibriumManila clamPerkinsosis

Identifiers

PMID42298410
PMCPMC13504780

What Socratic holds

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.