A 66-bp deletion in growth hormone releasing hormone gene 5 '-flanking region with largemouth bass recessive embryonic lethal

作者：Ma, D. M.; Han, L. Q.; Bai, J. J.^*; Li, S. J.; Fan, J. J.; Yu, L. Y.; Quan, Y. C.

来源：Animal Genetics, 2014, 45(3): 421-426.

DOI：10.1111/age.12143

• recessive lethal
• livability
• homozygous lethal
• Micropterus salmoides
• indel site

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 (Micropterus salmoides) GHRH gene. In two cultured random populations of adult individuals (A: n=170 and B: n=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 GHRH mRNA expression levels in brain tissue were detected using real-time PCR. The effects of genotype (+/-) on growth traits and GHRH mRNA expression were not significant. Although the cause of death was not clear, the results hint that the 66-bp deletion site in GHRH 5 '-flanking sequence significantly affects the livability in largemouth bass embryonic development.

• 出版日期2014-6
• 单位中国水产科学研究院; 中国水产科学研究院珠江水产研究所