An investigation of genetic fecundity variants in Faroese sheep Ein rannsókn av arvaligum fruktbæri hjá føroyskum seyði
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Published
Oct 30, 2025
Eva K. Hansen
Jens Ivan í Gerðinum
Dag Inge Våge
Svein-Ole Mikalsen
https://orcid.org/0000-0003-2568-1554
Svein-Ole Mikalsen
Abstract
Several genes have variants that impact fecundity in mammals. We sequenced parts of some genes with internationally known high-fecundity variants in sheep from the northern Faroese islands. No known variant was found. Other variants were found, but none could be linked to twin/multiple births. This was further investigated using 362 ewes from four flocks and a genotyping array containing 51,646 ovine SNPs. We previously used these data to show that the genetic distance among the animals were clearly related to geography (as islands). When analysing genetic variations against fertility (measured as present and historical single or multiple births), only a single SNP showed statistical significance, and this was located outside any known coding region. When the four flocks were individually analysed, a few SNPs showed statistical significance in one flock, but not in other flocks. This strongly indicated that the hits were random and not functionally linked to high fertility. Thus, we were not able to find any gene or genome region that could be linked to high fertility or fecundity in Faroese sheep.
Úrtak
Fleiri ílegur hava avbrigdir, ið hava ávirkan á fruktabærið hjá súgdjórum. Vit sekvenseraðu nakrar ílegur, sum í øðrum londum eru kendar fyri at hava avbrigdir, ið kunnu setast í samband við høgt fruktabæri, fyri at vita, um tær eisini vóru í seyði í norðara parti av Føroyum. Ongar av hesum frukta-bærisavbrigdum vórðu funnar í føroyska seyðinum. Onnur avbrigdir vóru tó funnin, men eingi av teimum kundu knýtast at fleirlembum. Vit kannaðu eisini 362 ær úr fýra høgum í Føroyum, har vit nýttu eitt íleguúrval (genotyping array) við 51.646 seyðavbrigdum (Single Nucleotide Polymorphisms, SNPs). Vit hava áður brúkt hesar dátur til at vísa, at arvafrøðiliga fjarstøðan ímillum seyðin er týðiliga knýttur at, hvørjari oyggj seyðurin kemur úr. Tá arvaligi munurin varð samanborin við fruktabæri (núverandi og søguligar ein- og fleirlembur), var tað bert eitt avbrigdi, sum var hagfrøðiliga týðandi, men hetta avbrigdið var uttan fyri nakað kent proteinkotandi øki. Tá ærnar í hvørjum av teimum fýra høgunum vórðu samanbornar sínámillum, vóru tað nøkur fá avbrigdi, sum vóru hagfrøðiliga týðandi í einum haga, men sum ikki vóru tað í hinum høgunum. Hetta er ein sterk ábending um, at hesin munurin er tilvildarligur, og hevur ikki veruligt samband við fruktbærið hjá føroyska seyðinum. Sostatt funnu vit onga ílegu ella íleguøki, sum kann setast í samband høgt fruktabæri ella lambatal hjá føroyskum seyði.
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Keywords
Sheep, Fertility, Fecundity, Genetic variants, QTL analysis, Fruktbari, fruktabæri, arvalig avbrigdir, avbrigdiskanning, QTL kanning, seyður
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Bodensteiner, K. J., Clay, C. M., Moeller, C. L., & Sawyer, H. R. (1999). Molecular cloning of the ovine Growth/Differentiation factor-9 gene and expression of growth/differentiation factor-9 in ovine and bovine ovaries. Biology of Reproduction, 60(2), 381–386. https://doi.org/10.1095/biolreprod60.2.381
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Charlesworth, D., & Willis, J. H. (2009). The genetics of inbreeding depression. Nature Reviews Genetics, 10, 783–796. https://10.1038/nrg2664
Curtin, L., D'Andrea, W. J., Balascio, N. L., Shirazi, S., Shapiro, B., de Wet, G. A., Bradley, R. S., & Bakke, O. (2021). Sedimentary DNA and molecular evidence for early human occupation of the Faroe Islands. Nature Communications Earth & Environment, 2, 253. https://doi.org/10.1038/s43247-021-00318-0
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Deng, J., Xie, X. L., Wang, D. F., Zhao, C., Lv, F. H., Li, X., Yang, J., Yu, J. L., Shen, M., Gao, L., Yang, J. Q., Liu, M. J., Li, W. R., Wang, Y. T., Wang, F., Li, J. Q., Hehua, E., Liu, Y. G., Shen, Z. Q.,…Li, M. H. (2020). Paternal origins and migratory episodes of domestic sheep. Current Biology, 30(20), 4085–4095 e4086. https://doi.org/10.1016/j.cub.2020.07.077
Dicuil. (825). Liber de mensura orbis terrae. Irland.
Dýrmundsson, Ó. R., & Niznikowski, R. (2010). North European short-tailed breeds of sheep: a review. Animal, 4, 1275–1282. https://doi.org/10.1017/S175173110999156X
Edwards, S. J., & Juengel, J. L. (2017). Limits on hogget lambing: the fertility of the young ewe. New Zealand Journal of Agricultural Research, 60(1), 1–22. http://dx.doi.org/10.1080/00288233.2016.125359
Effersøe, R. C. (1886). Landbruget og Husdyrbruget paa Færøerne samt Midler til Husdyrbrugets Fremme, utarbejdet paa det Kongelige danske Landhusholdningsselskabs Opfordring. Med Bemærkninger af Inspektør Feilberg (Agriculture and animal husbandry in the Faroe Islands and sources for the promotion of animal husbandry, prepared at the request of the Royal Danish Agricultural Society. With remarks from inspector Feilberg) Justitsministeriet. Kjøbenhavn (Copenhagen, Denmark). 60 pp. https://drive.reindex.net/FAOUTL/12/Effers%C3%B8e_landbruget.pdf
Gebreselassie, G., Berihulay, H., Jiang, L., & Ma, Y. (2019). Review on genomic regions and candidate genes associated with economically important production and reproduction traits in sheep (Ovies aries). Animals (Basel), 10(1), 33. https://doi.org/10.3390/ani10010033
Hanrahan, J. P., Gregan, S. M., Mulsant, P., Mullen, M., Davis, G. H., Powell, R., & Galloway, S. M. (2004). Mutations in the genes for oocyte-derived growth factors GDF9 and BMP15 are associated with both increased ovulation rate and sterility in Cambridge and Belclare sheep (Ovis aries). Biology of Reproduction, 70(4), 900–909. https://doi.org/10.1095/biolreprod.103.023093
Hansen, E. K., í Gerðinum, J. I., Våge, D. I., & Mikalsen, S. O. (2025). Faroese sheep expand overall global ovine genetic diversity. BMC Genomic Data, 26, 31. https://doi.org/10.1186/s12863-025-01319-0
ICLAS. The International Council for Laboratory Animal Science Ethical Guidelines for Researchers. https://iclas.org/guidelines-for-researchers/
International Consortium for Blood Pressure Genome-Wide Association, S., Ehret, G. B., Munroe, P. B., Rice, K. M., Bochud, M., Johnson, A. D., Chasman, D. I., Smith, A. V., Tobin, M. D., Verwoert, G. C., Hwang, S. J., Pihur, V., Vollenweider, P., O'Reilly, P. F., Amin, N., Bragg-Gresham, J. L., Teumer, A., Glazer, N. L., Launer, L.,…Johnson, T. (2011). Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk. Nature, 478(7367), 103–109. https://doi.org/10.1038/nature10405
Jensen Beder, N. (2010). Seyður, ull, tøting (Sheep, wool, fulling - In Faroese). Sprotin. Tórshavn, Faroe Islands. 337 pp.
Kumar, S., Stecher, G., & Tamura, K. (2016). MEGA7: Molecular evolutionary genetics analysis version 7.0 for bigger datasets. Molecular Biology and Evolution, 33(7), 1870–1874. https://doi.org/10.1093/molbev/msw054
Lagler, D. K., Hannemann, E., Eck, K., Klawatsch, J., Seichter, D., Russ, I., Mendel, C., Lühken, G., Krebs, S., Blum, H., Upadhyay, M., & Medugorac, I. (2022). Fine-mapping and identification of candidate causal genes for tail length in the Merinolandschaf breed. Communications Biology, 5(1), 918. https://doi.org/10.1038/s42003-022-03854-3
Larsson, M. N. A., Miranda, P. M., Pan, L., Vural, K. B., Kaptan, D., Soares, A. E. R., Kivikero, H., Kantanen, J., Somel, M., Özer, F., Johansson, A. M., Storå, J., & Günther, T. (2024). Ancient sheep genomes reveal four millenia of North European short-tailed sheep in the Baltic Sea region. Genome Biology and Evolution, 16, evae114. https://doi.org/10.1093/gbe/evae114
Logir.fo. (1990). Kunngerð nr. 141 frá 10. desember 1990 um fyribyrging av ridluskriða, sum seinast broytt við kunngerð nr. 178 frá 21. september 1993 (Announcement no. 141 from 10th December 1990 on prevention of scrapie, as latest revised by announcement no. 178 from 21st September 1993). Retrieved 4 June 2024 from https://logir.fo/Kunngerd/141-fra-10-12-1990-um-fyribyrging-av-ridluskrida-sum-seinast-broytt-vid-kunngerd-nr-178
Loos, R. J. F., & Yeo, G. S. H. (2022). The genetics of obesity: from discovery to biology. Nat Rev Genet, 23(2), 120–133. https://doi.org/10.1038/s41576-021-00414-z
Purcell, S., Neale, B., Todd-Brown, K., Thomas, L., Ferreira, M. A., Bender, D., Maller, J., Sklar, P., de Bakker, P. I., Daly, M. J., & Sham, P. C. (2007). PLINK: a tool set for whole-genome association and population-based linkage analyses. American Journal of Human Genetics, 81(3), 559–575. https://doi.org/10.1086/519795
Rochus, C. M., Jonas, E., & Johansson, A. M. (2020). Population structure of five native sheep breeds of Sweden estimated with high density SNP genotypes. BMC Genetics, 21(1), 27. https://doi.org/10.1186/s12863-020-0827-8
Rowntree, K., Duma, M., Kakembo, V., & Thornes, J. (2004). Debunking the myth of overgrazing and soil erosion. Land Degradation & Development, 15, 203–214. https://doi.org/10.1002/ldr.6
Sadleir, R. M. (1968). Reproductive responses to the environment in mammals. Journal of Psychosomatic Research, 12(1), 3–9. https://doi.org/10.1016/0022-3999(68)90003-2
Shad, F. I., Tufanil, N. A., Ganie, A. M., & Ahmed, H. A. (2011). Flushing in ewes for higher fecundity and fertility. Livestock International, 15(2), 10–11.
Skårup, P. (2009). Dicuil about the Faroe Islands (in Faroese). Fróðskaparrit, 57, 5–10. https://doi.org/10.18602/fsj.v57i.68
Svabo, J. C. (1789a). Om Faare-Arter (On Sheep Species). In Indberetninger, indhentede paa en, allernaadigst befalet, reise i Færøe i aarene 1781 og 1782 (Reports collected on a most graciously ordered travel in the Faroe Islands in the years 1781 og 1782) (Rentekammeret (The Danish Central Financial Administration/National Archive). Reprinted by Selskabet til Udgivelse av Færøske Kildeskrifter og Studier (1959). Page 201–202.
Svabo, J. C. (1789b). Om Fedlir (On high sheep mortality, mostly caused by harsh winters). In Indberetninger, indhentede paa en, allernaadigst befalet, reise i Færøe i aarene 1781 og 1782 (Reports collected on a most graciously ordered travel in the Faroe Islands in the years 1781 og 1782) (Rentekammeret (The Danish Central Financial Administration/National Archive). Reprinted by Selskabet til Udgivelse av Færøske Kildeskrifter og Studier (1959). Page 211–212.
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