Research Advances on Molecular Breeding of Groupers in China

Special Article - Molecular Breeding

Austin J Mol & Cell Biol. 2016; 3(1): 1008.

Research Advances on Molecular Breeding of Groupers in China

Yu H1†, You XX2† and Shi Q1,2,3*

¹BGI Education Center, University of Chinese Academy of Sciences, Shenzhen 518083, China

²Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, China

³Laboratory of Aquatic Genomics, College of Life Sciences and Oceanography, Shenzhen University, China †Equal contributors

*Corresponding author: Qiong Shi, Bldg 11 Room 618, Beishan Industrial Zone, BGI, Shenzhen 518083, China

Received: July 26, 2016; Accepted: August 23, 2016; Published: August 24, 2016

Abstract

As a group of economically important fish in China, groupers (Epinephelus spp.) are facing with insufficiency of high-quality gametes and germ plasm resource degradation. This situation has severely restricted the healthy development of grouper aquaculture. It is an inevitable choice to breed new varieties or species of groupers to solve these problems. Traditional hybridization and recently developed molecular breeding are effective ways to generate novel high-quality species of groupers. So far, several hybrid groupers have been cultivated in China with significant economic values. The important areas of molecular breeding include Marker-Assisted Selection (MAS) and transgenic breeding. At present, the molecular breeding of groupers in China is focusing on MAS breeding. We have constructed genetic linkage maps and carried out Quantitative Trait Loci (QTL) analysis for a couple of groupers. Furthermore, we have cooperated with scientists at Sun Yat-Sen University to sequence the whole genome of orange-spotted grouper (E. coioides). All these works will provide a valuable resource for understanding the genetic regulation of growth and establishing the foundation for MAS breeding in groupers.

Keywords: Groupers; Hybrid; Molecular breeding; Marker-assisted selection

Abbreviations

ddRAD: Double Digest Restriction-Site Associated DNA; GH/ IGF: Growth Hormone /Insulin-Like Growth Factor; GHRH: Growth Hormone-Releasing Hormone; GnRH: Gonadotropin- Releasing Hormone; MAS: Marker-Assisted Selection; MSG: Multiplexed Shotgun Genotyping; PRP-PACAP: PACAP-Related Peptide/Pituitary Adenylatecyclase Activating Polypeptide; QTL: Quantitative Trait Loci; SSR: Simple Sequence Repeat; SNP: Single- Nucleotide Polymorphism

Introduction

Groupers (Epinephelus spp.), a group of economically important marine fish species, are well-known for their rich nutrition, delicious taste and tender flesh [1,2]. Grouper industry has been developed rapidly in the past decades with wide cultivation of over 10 grouper species in China and South-East Asian countries [2]. Among them, E. coioides, E. akaara, E. awoara, and E. malabaricus are the main cultured species in China (Figure 1). In the last year, the yearly output of groupers in China is 100,006 tons, and the production of major cultured provinces, including Guangdong, Fujian and Hainan, are 42,601, 26,905, and 26,785 tons respectively [3]. At the same time, degeneration of germ plasm resources, decrease of genetic diversity and degradation of gamete quality have been threatening the development and progress of grouper industry. During the past decade, rapid development of genomic biotechnology and increasing focuses on more efficient selection programs have accelerated genetic improvement in groupers. The high throughput sequencing techniques have facilitated identification of efficient molecular markers and implementation of Marker-Assisted Selection (MAS) program.MAS breeding is going to become a prospective strategy for generation of ideal novel species of fish. Both construction of genetic linkage maps and identification of Quantitative Trait Loci (QTL) will lay the foundation for the development of MAS program in groupers. Meanwhile, traditional hybridization breeding has created several ideal grouper hybrids, which provide genetic resources for understanding the molecular mechanisms of growth superiority in the hybrid groupers.