A 66‐bp deletion in growth hormone releasing hormone gene 5′‐flanking region with largemouth bass recessive embryonic lethal. (3rd April 2014)

• Record Type: Journal Article
• Authors: Ma, D. M.; Han, L. Q.; Bai, J. J.; Li, S. J.; Fan, J. J.; Yu, L. Y.; Quan, Y. C.
• Is Part Of: Animal genetics. Volume 45:Number 3(2014:Jun.)
• Page Start: 421
• Page End: 426
• Publication Date: 2014-04-03
• Subjects: Animal genetics -- Periodicals; 572.8
• DOI: 10.1111/age.12143
• Languages: English
• ISSNs: 0268-9146

Abstract

<abstract abstract-type="main" id="age12143-abs-0001"> <title>Summary</title> <p>Growth hormone releasing hormone (GHRH) regulates the secretion of growth hormone (GH) in the pituitary gland. A 66‐bp deletion (c.‐923_‐858del) was detected in the 5′‐flanking sequence of the largemouth bass (<italic>Micropterus salmoides</italic>) <italic>GHRH</italic> gene. In two cultured random populations of adult individuals (A: <italic>n </italic>=<italic> </italic>170 and B: <italic>n </italic>=<italic> </italic>150), the genotype ratios of +/+:+/− were 2.5:1 and 2.8:1 respectively. Only one −/− fish was detected. A Largemouth bass family was constructed with two heterozygous individuals (+/−) as parents. The genotype ratio of +/+:+/−:−/− in the filial generation embryos was 1:1.6:0.1 at the neurula and 1:2:0 at hatched larvae stages. This indicated that the 66‐bp deletion was a recessive lethal site and that homozygous individuals (−/−) died off in embryonic development. The growth traits (body weight, body length and body depth) were measured, and the <italic>GHRH</italic> mRNA expression levels in brain tissue were detected using real‐time PCR. The effects of genotype (+/−) on growth traits and <italic>GHRH</italic> mRNA expression were not significant. Although the cause of death was not clear, the results hint that the 66‐bp deletion site in <italic>GHRH</italic> 5′‐flanking sequence significantly affects the livability in largemouth bass embryonic development.</p> </abstract>