Polymorphism in exon 4 of snakehead fish (Channa striata) growth hormone gene from sumatra (indonesia) and its association with growth traits

Growth hormone (GH) gene can be used for selection in some aquaculture species for the best phenotypic performance during farming. This research investigated the polymorphism of the GH gene and its association with growth traits of snakehead fish. 253 snakehead fish were collected from 9 locations in Sumatra (Indonesia), i.e. rivers, lake, and floodplains. 27 were used for DNA isolation. The morphology data set included body weight (W), standard length (SL), body height (BH), length of the dorsal fin (pinna dorsalis-PD), length of the anal fin (pinna analis-PA), head length (HL), head width (HW), SL/BH, SL/PD, SL/AD, SL/HL, and SL/HW for all specimens. Exon 4 of the GH gene was amplified with PCR and sequenced to determine the possible occurrence of polymorphisms on the exon from each specimen. This exon was amplified at approximately 116-128 bp in size. Moreover, the gene alignment showed the polymorphism existence in the form of insertion, deletion (indel) and Single Nucleotide Polymorphism (SNP). Insertion-deletion were recorded in almost all specimens. However, only a few numbers of specimens showed SNP occurrences. Growth traits (SL, W, PD, PA, HL, and HW) of snakehead fish were high in Kampar River (SK), Lubuk Lampam River (LL), and Merang River, and significantly different (p<0.05). The polymorphism affected the SL, W and HW, with a coefficient correlation between 0.4-0.421. There was no change in the amino acids of SNP, while changes occurred at the indel. Polymorphisms significantly affected (p<0.05) SL (25.22±3.14) and HW (3.42±0.48). The high polymorphism scores (between 0-3) were observed in SK and SM. Exon 4 GH has a potential to be utilized as marker of growth traits for snakehead by augmenting the specimen and using other regions of the GH gene for further study. © 2020, BIOFLUX SRL. All rights reserved.