DNA and Jian Carp

Decoding Fish Growth: Can Genetics Help Us Breed Better Carp?

Author's portrait.
Rhea Morgan in Science & Nature December 2025 • 4 min read.

"Unlocking the secrets of leptin genes in Jian carp could revolutionize aquaculture, offering faster growth and more sustainable fish farming practices."


For centuries, breeders have sought to enhance desirable traits in livestock through selective breeding. Now, modern genetics offers powerful new tools to accelerate this process. In aquaculture, where efficient growth is paramount, understanding the genetic factors that influence size and weight can lead to significant improvements in fish production.

Leptin, a hormone known for its role in regulating appetite and metabolism, has emerged as a key player in growth regulation in various animals. Research has revealed that variations in the leptin gene can influence body weight, energy expenditure, and food intake. This makes it a prime target for investigation in fish species, where growth rates directly impact economic viability.

This article explores how a recent study investigated the link between variations in the leptin gene and growth traits in Jian carp (Cyprinus carpio var. Jian), a widely cultured fish in China. By identifying specific genetic markers associated with faster growth, this research opens doors to developing marker-assisted selection (MAS) programs, ultimately leading to more efficient and sustainable aquaculture practices.

Leptin's Genetic Code: How It Impacts Carp Growth

DNA and Jian Carp

The study focused on Jian carp, a popular aquaculture species, examining two leptin genes, jlLEP-A1 and jlLEP-A2. Researchers looked for single nucleotide polymorphisms (SNPs) – tiny variations in the DNA sequence – within these genes. These SNPs can act as signposts, indicating regions of the genome that influence specific traits.

The researchers identified three key SNPs in the jlLEP-A1 and jlLEP-A2 genes:

  • jlLEP-A1 (A1-T113C): A change at position 113 in the jlLEP-A1 gene.
  • jlLEP-A2 (A2-G415A): A change at position 415 in the jlLEP-A2 gene.
  • jlLEP-A2 (A2-G427A): A change at position 427 in the jlLEP-A2 gene.
They then analyzed the association between these SNPs and growth traits in a population of over 500 Jian carp, categorizing fish by their SNP genotypes and measuring their body weight gain during juvenile and adult stages. The results revealed that these SNPs were indeed linked to growth, but the effects differed between males and females. Specifically, all three SNPs significantly impacted growth traits in male Jian carp, while only one SNP (A1-T113C) showed a significant association in females. Further analysis revealed specific combinations of SNPs (diplotypes) within the jlLEP-A2 gene also correlated with growth performance in males.

Breeding Better Fish: The Future of Jian Carp Aquaculture

This research demonstrates the potential of using genetic markers to improve growth rates in Jian carp. By identifying specific SNPs and diplotypes associated with faster growth, breeders can selectively breed fish with these favorable genetic traits, accelerating the process of improving overall stock performance.

Marker-assisted selection (MAS) offers a more efficient and targeted approach compared to traditional breeding methods. Instead of relying solely on observable traits, MAS allows breeders to identify and select fish with desired genetic profiles early in their development. This can significantly reduce the time and resources required to breed faster-growing fish.

While this study provides valuable insights into the role of leptin genes in Jian carp growth, further research is needed to explore the interplay of multiple genes and environmental factors. Ultimately, a comprehensive understanding of the genetic architecture of growth will pave the way for even more effective and sustainable aquaculture practices, not just for Jian carp, but for other commercially important fish species as well.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.4238/gmr.15037635, Alternate LINK

Title: Association Study Between Single Nucleotide Polymorphisms In Leptin And Growth Traits In Cyprinus Carpio Var. Jian

Subject: Genetics

Journal: Genetics and Molecular Research

Publisher: Genetics and Molecular Research

Authors: Y. Tang, H. Li, J. Li, F. Yu, J. Yu

Published: 2016-01-01

Everything You Need To Know

1

Which leptin genes and SNPs were studied in Jian carp to understand growth?

The study focused on Jian carp, examining two leptin genes, specifically *jlLEP-A1* and *jlLEP-A2*. Researchers looked for single nucleotide polymorphisms (SNPs) – tiny variations in the DNA sequence – within these genes. The three key SNPs identified were *jlLEP-A1* (A1-T113C), *jlLEP-A2* (A2-G415A), and *jlLEP-A2* (A2-G427A).

2

How do variations in the *jlLEP-A1* and *jlLEP-A2* genes affect the growth of Jian carp, and are there differences between males and females?

Variations in the *jlLEP-A1* and *jlLEP-A2* genes, specifically single nucleotide polymorphisms (SNPs) like A1-T113C in *jlLEP-A1*, and A2-G415A and A2-G427A in *jlLEP-A2*, have been linked to differences in growth rates in Jian carp. The effects varied between males and females, with all three SNPs impacting growth in males and only A1-T113C showing a significant association in females. Specific combinations of SNPs (diplotypes) within the *jlLEP-A2* gene also correlated with growth performance in males.

3

How can marker-assisted selection (MAS) using SNPs in the *jlLEP-A1* and *jlLEP-A2* genes improve breeding programs for Jian carp?

Marker-assisted selection (MAS) is a breeding strategy where breeders select fish based on the presence of specific genetic markers, like the SNPs in the *jlLEP-A1* and *jlLEP-A2* genes of Jian carp. If a fish has the A1-T113C, A2-G415A or A2-G427A variants, which are associated with faster growth (especially in males), breeders can preferentially breed those fish to improve the growth rates of subsequent generations.

4

Besides growth, what other biological processes are influenced by the leptin genes *jlLEP-A1* and *jlLEP-A2* in Jian carp, and how might this affect breeding strategies?

Leptin, specifically the *jlLEP-A1* and *jlLEP-A2* genes in Jian carp, plays a role in regulating appetite and metabolism. Therefore, variations in these genes can lead to changes in how the fish process energy and grow. By identifying and selecting for specific SNPs within these leptin genes, breeders can potentially influence these metabolic pathways to optimize growth rates.

5

What are the broader implications of understanding the genetics of leptin, specifically the *jlLEP-A1* and *jlLEP-A2* genes in Jian carp, for sustainable aquaculture practices?

This research has implications for sustainable aquaculture practices of Jian carp, because understanding the link between variations in *jlLEP-A1* and *jlLEP-A2* genes and growth traits can lead to more efficient and sustainable fish farming practices. By identifying specific SNPs and diplotypes associated with faster growth, breeders can selectively breed fish with these favorable genetic traits, accelerating the process of improving overall stock performance. This can lead to reduced feed consumption, faster time to market, and overall improved resource utilization in Jian carp aquaculture.

Newsletter Subscribe

Subscribe to get the latest articles and insights directly in your inbox.