1 Introduction

Among the major farmed species worldwide, the Nile tilapia (Oreochromis niloticus) and the Mozambique tilapia (O. mossambicus) have become important aquatic economic species due to their rapid growth, strong environmental adaptability and outstanding reproductive ability. These fish species supply important protein resources for developing regions and are of strategic significance for ensuring food security and promoting regional economic development (Tao et al., 2013; Celino-Brady et al., 2022; Celino-Brady et al., 2022.

Analyzing the development mechanism of gonads is the key to improving the efficiency of aquaculture. This species adopts the XX/XY sex determination system, and gonadal differentiation involves the synergistic effect of genetic regulation and hormones. Gender characteristics (such as growth differences and reproductive morphology) result from the synergistic effect of developmental programs and endocrine regulation (such as growth hormone GH, luteinizing hormone LH) (Ijiri et al., 2008; Celino-Brady et al., 2022; Celino-Brady et al., 2022). Clarifying these biological processes is helpful for optimizing breeding programs, regulating the sex ratio and increasing aquaculture productivity (Tao et al., 2013).

Modern genomic technology has revolutionized the study of gender differentiation. The combined analysis technology of RNA sequencing and miRNA-mRNA can systematically track the gene dynamics and regulatory network of gonadal development (Tao et al., 2013; Tao et al., 2018; Wei et al., 2016; Wang et al., 2019; Tao et al., 2016; Wang et al., 2016). The study revealed the differential expression patterns of key genes (Cyp19a1a, Foxl2, Dmrt1, etc.) and regulatory Rnas in the gonads, and clarified their effects on hormone synthesis and sexual maturity. These findings have deepened the understanding of the sex determination mechanism and laid the foundation for the development of gene regulation technologies.

This study revealed the molecular mechanisms of sex development in tilapia by analyzing the expression profiles of gonadal genes. It integrates cutting-edge transcriptome data, systematically evaluates core regulatory factors and their interaction networks, and proposes application strategies for upgrading the aquaculture industry. The study provides an overview of the biological characteristics and reproductive mechanisms of tilapia, explores scientific breakthroughs in genomic technology, compares the gene expression characteristics of gonadal tissues, and looks forward to future research directions and their potential for transformation in fisheries innovation.

2 Tilapia Sex Determination Mechanism

2.1 Characteristics of genetic sex determination system

Tilapia presents diverse sex determination mechanisms, including two systems: male mating (XX/XY) and female mating (ZZ/ZW). The Nile Tilapia (Oreochromis niloticus) and Tilapia zillii adopt the XX/XY system, and their male individuals carry sex-related gene clusters in linkage group 1 (LG1). In contrast, the ZZ/ZW systems of Oreochromis karongae and Tilapia mariae have female-specific genetic elements in LG3. Hybrids such as the Orian tilapia (O. aureus) and the Mozambican tilapia (O. mossambicus) exhibit a polygenic regulatory pattern of LG1 and LG3 interaction (Cnaani et al., 2008; Wohlfarth and Wedekind, 1991;  Zhu et al., 2022;  Taslima et al., 2021).

This genetic complexity manifests as multi-regional synergy. The Nile tilapia population has key sex determination loci in both LG1 and LG23, among which the Amhy gene of LG23 drives the male differentiation of specific strains. By inhibiting gene recombination and maintaining these regions with sex-specific survival advantages, tilapia has become an ideal model for the study of sex chromosomes in vertebrates (Cnaani et al., 2008; Zhu et al., 2022; Taslima et al., 2021).

2.2 Core regulatory gene network

The Dmrt1 gene is a core regulatory factor for male differentiation - its inactivation can lead to the arrest of testis development, even if other male-related genes are expressed normally. Although Amhy and gSDF are involved in testicular formation, their functions can be compensated by mutations in female developmental genes, while the role of Dmrt1 is irreplaceable (Qi et al., 2024).

The female developmental pathway depends on the Cyp19a1a (estrogen synthase), Foxl2 and foxl3 genes. The dynamic balance of Dmrt1 (promoting testicular growth) and foxl3 (promoting ovarian growth) determines the specialization of germ cells and forms the environmental sensitivity of sex determination. This genetic plasticity enables external conditions to influence phenotypic gender, reflecting the synergistic regulation of genes and the environment. The estrogen produced by Cyp19a1a further activates ovarian development, highlighting the key functions of these genes (Nagahama, 2005; Dai et al., 2021; Qi et al., 2024).

2.3 Regulatory role of environmental factors

Temperature exposure during the critical period of development significantly alters the sex ratio, and high-temperature environments significantly increase the proportion of males. Genetic breeding can change temperature sensitivity - the male rate of highly sensitive strains reaches 90% within two generations, while there is no significant change in low-sensitive strains (Baroiller et al., 2009).

Endocrine signals can also regulate gender phenotypes. The estrogen produced by natural Cyp19a1a initiates ovarian development, while artificial hormone treatment can reverse genetic sex determination. The interaction between Dmrt1 and FOXL3 enables germ cells to respond to environmental signals such as temperature or hormones, confirming that gender characteristics are regulated by both genes and the environment (Baroiller et al., 2009; Nagahama, 2005; Dai et al., 2021; Qi et al., 2024).

3 Analysis of the Differences in Gonad Transcriptome between male and female Tilapia

3.1 Practice of RNA sequencing technology in gonad research

Gene sequencing technology has now become the core tool for analyzing the gene expression characteristics of tilapia gonads and can systematically track the transcriptional dynamics during the development of gonads. By comparing the gonadal transcription data of XX and XY individuals at different growth stages, researchers constructed a gene expression map during the process of sexual maturity (Tao et al., 2013; Tao et al., 2018). This technology can not only detect known RNA molecules, but also identify novel transcripts, providing key data support for revealing the formation mechanism of gender characteristics (Jin and Liu, 2024).

The integration of mRNA-miRNA joint analysis has deepened the understanding of the gender regulatory network. The study identified multiple mirnas related to steroid metabolism and reproductive function, and verified their target genes through techniques such as quantitative PCR. This multi-dimensional verification strategy significantly enhances the credibility of research results by confirming the association between gene expression patterns and physiological functions (Ijiri et al., 2008; Eshel et al., 2014; Tao et al., 2016; Teng et al., 2020; Teng et al., 2021).

3.2 Expression characteristics of gender-related genes

Comparative analysis shows that there are significant differences in the expression of gonadal genes between the sexes, especially at key developmental stages. The study found over 1,300 sex-differentially expressed genes in tilapia, including 259 genes highly expressed in males and 69 genes specifically expressed in females (Tao et al., 2013; Tao et al., 2018). These differences are particularly prominent in key events such as the initiation of ovarian meiosis and testicular cell specialization (Ijiri et al., 2008).

The core differentially expressed genes involve steroid metabolism regulatory factors (Cyp19a1a, cyp11b2), transcriptional regulatory elements (Foxl2, Dmrt1), and gamete developation-related genes (sox9, amh). These genes not only mark the status of sex differentiation, but also directly regulate the process of gonadal maturation. Furthermore, gender-related mirnas and their target genes exhibit hierarchical regulatory characteristics during gonadal development (Tao et al., 2016; Eshel et al., 2014).

3.3 Reproductive regulatory functions of gender-related genes

The sex-specific genes identified by transcriptome are mainly involved in reproductive regulation, hormone metabolism and germ cell development. Ovarian tissue drives estrogen synthesis and follicular development by activating Cyp19a1a and Foxl2 genes, while testicular tissue upregulates Dmrt1, sox9 and amh genes to promote sperm production (Tao et al., 2013; Tao et al., 2018; Ijiri et al., 2008; Eshel et al., 2014). These core regulatory elements maintain the stability of gender characteristics during the stage of sexual maturity.

The study also found that TGF-β/Wnt signaling elements and auxiliary pathways such as steroid synthase are involved in the regulation of sex differentiation (Bohne et al., 2014; Tao et al., 2016). Multi-level pathway analysis involving hormone synthesis, cell proliferation and epigenetic modification revealed the complex regulatory network of sex development, providing a theoretical basis for aquatic reproduction management (Tao et al., 2013; Bohne et al., 2014; Eshel et al., 2014; Tao et al., 2018).

4 Analysis of the Transcriptome Characteristics of Male Tilapia gonads

4.1 Genes related to spermatogenesis and androgen production

Male gonad tissues show high expression characteristics of genes regulating sperm production, involving the processes of germ cell proliferation and sperm formation. The testicle-specific gene igf3 promotes the proliferation and differentiation of spermatogonia and the formation of spermatocytes. Knocking out this gene can lead to sperm development disorders and decreased fertility, while overexpression enhances sperm production, confirming its core reproductive function (Li et al., 2020). The Sox30 gene specifically acts on spermatogenic cells and activates essential genes for sperm maturation such as ift140 and ptprb. The inactivation of this gene causes structural defects and decreased motility of sperm, highlighting its importance to reproductive success (Wei et al., 2021).

Androgen synthesis genes show a peak in activity during the critical period of development. The Cyp11b2 gene, which is responsible for generating the potent androgen 11-keto testosterone, is significantly highly expressed in the male gonads starting from 35 days after incubation, and is synchronized with testicular differentiation and the initiation of sperm production (Ijiri et al., 2008). This hormone level change drives the development of male characteristics and the establishment of reproductive ability (Tao et al., 2013).

4.2 Specifically activated signaling pathways

The male gonads show activation of specific pathways that support testicular function. The amh pathway regulates the number of germ cells - inhibiting this pathway disrupts testicular development, reduces sperm count and alters hormonal regulatory patterns. Abnormal Amh function also affects TGF-β and Wnt signaling, which regulate the cell proliferation and growth processes necessary for spermatogenesis (Yan et al., 2022).

The expression of Sox9 is enhanced in the later stage of testicular maturation and participates in the maintenance of tissue structure and functional stability (Ijiri et al., 2008). Meanwhile, components of the Wnt pathway regulate cell division during the sperm development stage. These systems, together with TGF- β and FoxO signals, constitute the interaction network regulating the maturation of male reproductive tissues (Figure 1) (Thonnes et al., 2022; Yan et al., 2022).

Figure 1 Down-regulation of amh inhibited development of sex organs and testis tissues in male Nile tilapia (Adopted from Yan et al., 2022) Image caption: (A) Effect of down-regulated amh in treatment group; (B) male fish in control group; (C) Comparison of testis tissue between treatment group and control group (Adopted from Yan et al., 2022)

4.3 Male-specific transcriptional regulatory factors

The testicular tissue selectively activates the transcription factors that regulate male development. Dmrt1 dominates the early stage of the gonads and regulates the initial differentiation of the testicles (Ijiri et al., 2008). In the later stage of development, the activities of sox9 and amh are enhanced, strengthening the characteristics of male tissues.

Another key factor, Sox30, acts on spermatogenic precursor cells and activates the essential genes for sperm terminal maturation. This gene mutation can block the activation of the target gene, resulting in sperm deformity and reduced reproductive capacity (Wei et al., 2021). The synergistic effect of these regulatory factors ensures the normal development and sustained reproductive capacity of sperm.

5 Analysis of the Characteristics of the gonad transcriptome of Female Tilapia

5.1 Key genes for ovarian development and egg maturation

Female gonadal function depends on specific genes that regulate follicular development and oocyte maturation. gSDF, a component of the TGF-β pathway, plays a crucial role in maintaining the ovaries. The deficiency of its function can lead to an infertile phenotype characterized by follicular development arrest and accumulation of immature oocytes. The dysregulation of the genes related to this pathway (increased expression of amh/amhr2 and decreased expression of inhbb/acvr2a) confirmed that TGF-β signaling is involved in the regulation of oogenesis (Jiang et al., 2022).

The Amh gene simultaneously regulates the dynamic changes of follicles. Inhibiting the expression of Amh will delay the process of ovarian maturation, increase the proportion of oocyte degeneration, and reduce the activities of genes such as amhrII and Cyp19a1a. These changes, accompanied by decreased reproductive hormone levels and abnormal oocyte development, highlight the importance of Amh in female reproduction (Qiang et al., 2022; Chen, 2024). The above-mentioned genes jointly constitute the ovarian physiological regulatory axis.

5.2 The core function of Cyp19a1a in estrogen synthesis

Cyp19a1a encoding aromatase drives the synthesis of estrogen in female gonads. This gene reaches its peak expression level in the early stage of ovarian differentiation and promotes the production of estradiol-17 β, which is essential for female development (Ijiri et al., 2008; Tao et al., 2013). Foxl2 directly activates Cyp19a1a transcription. Inactivation of either gene leads to a sudden drop in estrogen levels and triggers masculinization in XX individuals, confirming that the two cooperatively maintain ovarian characteristics (Li et al., 2013; Zhang et al., 2017).

The antagonistic effect of Foxl2 against Dmrt1 further regulates estrogen synthesis. The deletion of Foxl2 or Cyp19a1a not only reduces estrogen levels but also activates male development genes, revealing that estrogen has the dual functions of inhibiting the testicular pathway and promoting ovarian maturation (Li et al., 2013; Zhang et al., 2017).

5.3 Ovarian specific signaling network (TGF-β/BMP Pathway)

The female gonads mainly rely on the TGF-β and BMP pathways to perform reproductive functions. The TGF-β system mediated by gSDF and amh regulates the developmental processes such as follicular growth, recruitment and atresia. Knockout of gSDF disrupts the TGF-β gene network and blocks oocyte maturation, confirming its necessity for reproductive capacity (Figure 2) (Jiang et al., 2022).

Figure 2  Morphological and histological analyses of ovaries (A) and spawning frequency (B) from XX gsdf+/+ and gsdf-/- tilapia (Adopted from Jiang et al., 2022) Image caption: The fish were dissected at 6 and 24 mah. Results are presented as mean±SD. *and indicate significant differences at P<0.05 and P<0.01, respectively. (B) The spawning frequency of months old XXgsdf+/+ and gsdf-/- fish were observed for half a year. More than ten XXgsdf-/- fish were observed for spawning, while none reproduced (Adopted from Jiang et al., 2022)

The BMP signal components also affect the follicular quality and development process. Gene expression analysis revealed that BMP-related genes in ovarian tissues presented a differential expression pattern, suggesting their optimization effect on reproductive performance (Jiang et al., 2022). The synergistic effect of the TGF-β/BMP cascade reaction, hormone regulation and genetic control jointly ensures the synchronous progress of oogenesis and ovarian homeostasis.

6 Analysis of the Coexpression Network and Metabolic Pathways of Tilapia gonads

6.1 Identification of gender-related gene groups based on WGCNA

Gene Co-expression network analysis technology (WGCNA) provides an effective tool for exploring the gene population related to sex differentiation in tilapia and its regulatory system. By analyzing the gene expression data of gonads, this method functionally grouped based on the collaborative activity patterns of genes and successfully identified the gene sets closely related to the development of the male and female reproductive systems. This technology has been successfully applied in aquatic product research and can precisely locate the gene modules and core regulatory factors related to gender characteristics (Zhou et al., 2019).

Combined with the analysis of the miRNA-mRNA interaction network, WGCNA can systematically reveal the regulatory mechanism of the sexual maturation process of tilapia. This multi-dimensional analysis method not only detects protein-coding genes, but also tracks the role of non-coding Rnas (such as mirnas and circular Rnas) in the sex regulatory network, significantly enhancing the understanding of gonadal differentiation and the formation mechanism of sex characteristics (Tao et al., 2016; Zhong et al., 2022).

6.2 Key biological functions and metabolic pathways

Through gene function annotation (GO) and pathway enrichment analysis (KEGG), researchers discovered important biological features in the gonads of tilapia. Studies have shown that gene groups related to circular RNA and miRNA present significant enrichment phenomena in reproductive system functions (such as cell junctions, androgen production, and steroid transformation) (Tao et al., 2016; Zhong et al., 2022).

KEGG analysis revealed the core regulatory systems, including the regulation of oocyte development, progesterone signaling, cell division control and gonadotropin signaling pathways. These findings not only clarify the multi-level regulatory characteristics of gender differentiation, but also point out the key directions for subsequent experimental verification (Jiang et al., 2024).

6.3 Core regulatory systems and key genes

The co-expression network and interaction analysis can precisely locate the functional units related to gonadal maturation. These modules contain highly connectivity hub genes that maintain network stability, such as the Dmrt1 gene necessary for male development and steroid synthesy-related gene groups (Tao et al., 2016; Zhou et al., 2019).

Studies have confirmed that specific mirnas constitute core nodes in regulating the gender differences of reproductive regulatory factors (Cyp19a1a, Foxl2, Dmrt1, gSDF). The functional analysis of these regulatory units and their constituent factors not only clarifies the molecular basis of sex determination, but also provides theoretical support for the development of sex control technologies in aquaculture (Tao et al., 2016; Zhong et al., 2022).

7 Characteristics of Sex-Related Non-Coding RNA in Tilapia Gonads

7.1 Gender differential expression of miRNA and lncRNA

The distribution characteristics of non-coding Rnas with significant gender differences during the development of tilapia gonads, especially mirnas and long non-coding Rnas (lncrnas), are the most typical. Studies have shown that a total of 635 mirnas were detected in gonadal tissues, among which 62 were highly expressed in females and 49 were dominant in males. These mirnas are involved in the process of gender characteristic formation by targeting and regulating important reproductive genes such as Cyp19a1a, Foxl2, and Dmrt1 (Tao et al., 2016). lncRNA also shows gender-specific expression patterns. The comparative experiments revealed that there were 962 differentially expressed lncrnas between the normal gonads and sex-reversed gonads of Nile tilapia, including 757 types with enhanced expression and 221 types with weakened expression. The lncRNA profiles of sex-reversed tissues show expression characteristics similar to those of the XY type, confirming their association with the maintenance of gonad phenotypes (Cai et al., 2019).

7.2 Interaction Mechanism between Non-coding Rnas and Reproductive Genes

Gender-related mirnas regulate the process of sexual development by inhibiting the activities of target genes. Typically, miR-96 and miR-737 coordinate the steroid production pathway through multiple targeting (Cyp19a1a, Foxl2, etc.), thereby influencing the direction of sex differentiation (Tao et al., 2016).

lncRNA participates in sex development through regulation at the genomic level. During the hormone-induced sex reversal process, the expression changes of lncRNA occur synchronously with the activity alterations of adjacent genes (such as cell connection-related genes). These molecules may indirectly regulate the sex-related gene network by regulating epigenetic characteristics or absorbing miRNA, etc. (Cai et al., 2019).

7.3 Functional verification and research development directions

Experimental evidence confirms the sex regulatory function of non-coding RNA. Quantitative experiments have shown that lncRNA presents conserved expression patterns during natural development and artificial sex reversal, confirming its biological value (Cai et al., 2019). The cross-species conservation of miRNA sequences in fish further supports their core regulatory functions (Tao et al., 2016).

Subsequent studies need to focus on analyzing the molecular mechanism of action, including target verification and the construction of interaction networks. In-depth exploration of the regulatory relationship among miRNA, lncRNA and functional genes will improve the theoretical system of sexual development and promote technological innovation in sex control of aquatic products (Tao et al., 2016; Cai et al., 2019).

8 The Application Value of Tilapia Gonad Transcriptome Research

8.1 Early Gender Identification and all-male population breeding

Gene expression research provides technical support for the development of gender-specific biomarkers (including genes and mirnas). Studies have found that mirnas associated with genes such as Cyp19a1a and Dmrt1 show differential expression patterns in the early development of XX and XY gonads and can achieve gender discrimination before morphological differentiation (Tao et al., 2013; Tao et al., 2016). This technology helps the aquaculture industry establish an all-male population - this strategy can enhance growth rate and uniformity of size, and has significant commercial value.

Genetic markers based on the amh gene region can improve the efficiency of unisexual breeding. Molecular marker-assisted breeding techniques (such as MAS-GMT) utilize these markers to rapidly screen genetic male individuals and achieve large-scale production of male fish fry required for industrial aquaculture (Caceres et al., 2019; Tao et al., 2022; Zhu et al., 2022).

8.2 Genetic markers and breeding Targets for trait improvement

Integrated genomic analysis technology can identify genetic markers and candidate genes related to gender and growth traits. Genome-wide association analysis revealed that SNP loci in the amh region and the QTL interval drive male development, supporting the precise molecular marker breeding program (Caceres et al., 2019; Zhu et al., 2022. High-density genetic maps and molecular marker systems accelerate the breeding process of superior traits. In addition to gender control, the study also identified growth-related genes such as dusp2 and rtn4r as breeding targets. Incorporating these target genes into the breeding system and screening individuals with excellent growth performance can significantly enhance the breeding productivity (Wang et al., 2024).

8.3 Targeted breeding application of gene editing technology

Functional genomic studies identified key genes such as Amh and Cyp19a1a as genetic manipulation targets. The CRISPR/Cas9 technology has been successfully applied to the gene-directed editing of tilapia, achieving controllable sex ratio and optimized growth characteristics (Li and Wang, 2017; Li et al., 2020). The mature experimental process covers the entire process from gene editing design to the establishment of mutant strains. The verification of target genes supports the practice of precise breeding and promotes the cultivation of high-yield, fast-growing, disease-resistant and controllable breeding lines. This method significantly improves the sustainability and economic benefits of aquaculture.

9 Current Challenges and Future Breakthroughs

9.1 Data heterogeneity, missing annotations and technical bottlenecks

The reproductive research of tilapia is difficult to reproduce due to differences in genetic strains, environmental variables and experimental protocols. Temperature fluctuations, developmental stages and genetic diversity significantly alter gene expression characteristics, causing data contradictions among studies and restricting comparative biological analysis (Sun et al., 2018; Yao et al., 2022). The complexity of the gene regulatory network - involving thousands of differentially expressed genes and non-coding RNA elements - further increases the difficulty of analysis (Tao et al., 2016; Zhong et al., 2022).

Insufficient annotation of bioinformatics constitutes a research bottleneck. Most genetic elements (especially non-coding Rnas and genetic isomers) lack functional annotation, coupled with the scarcity of genetic data for non-model species, which seriously hinders the verification of gene functions and pathway analysis (Tao et al., 2016; Wei et al., 2016; Zhong et al., 2022).

9.2 Requirements for temporal dynamics and spatial specificity analysis

Fine monitoring of gene expression dynamics during reproductive development still holds crucial value. Core regulatory factors (such as Cyp19a1a and Dmrt1) show temporal-dependent expression characteristics, and it is necessary to distinguish the initial sex determination signal from the subsequent effects through long-term tracking (Wei et al., 2016; Tao et al., 2013; Ijiri et al., 2008).

Spatially specific parsing is equally important. Some members of the Sox gene family show functional heterogeneity in different tissues (neural tissues and reproductive organs), highlighting the necessity of mapping tissue-specific gene expression profiles (Wei et al., 2016). Improving the spatio-temporal resolution will optimize the modeling accuracy of the gene network and facilitate the identification of key regulatory nodes.

9.3 Multi-dimensional omics integration research pathway

Integrating genomic data with epigenetic regulation, protein interaction networks and metabolomic characteristics is the core direction for advancing tilapia research. For example, DNA methylation studies have revealed that heat stress affects sex determination through epigenetic modifications, confirming the regulatory mechanism of environmental factors on genetic programs (Yao et al., 2022; Wang et al., 2018.

Proteomic and metabolomic association analysis can verify gene expression data and clarify biological processes such as hormone synthesis and neural signal transduction (Yao et al., 2022; Zhong et al., 2022). The fusion of multi-omics data will reveal new regulatory mechanisms and provide theoretical support for the development of precision breeding technologies.

10 Concluding Remarks

Analysis of the transcriptome of tilapia gonads revealed a large number of differential gene expression patterns involved in sex differentiation. Experiments on Nile tilapia have found that there are hundreds of sex-related genes at different developmental stages, including 259 male-specific genes, 69 female-specific genes and multiple highly expressed genes in males. The formation of female ovaries requires the early activation of estrogen synthases (such as Cyp19a1a), while the development of male testicles depends on the subsequent activation of androgen-related genes. Among the key regulatory factors, Foxl2 and Cyp19a1a jointly dominate the female pathway, while Dmrt1, sox9 and amh collaboratively regulate male development, verifying their core functions in gonadal differentiation.

Gender-related non-coding Rnas (especially mirnas) regulate hormone production and reproductive-related gene activities during important developmental periods. Epigenetic mechanisms such as DNA methylation regulate sex development pathways. For example, methylation differences have been detected in the Cyp19a1a gene that maintains gonadal characteristics. These studies have constructed a molecular map of tilapia sex maturity and deepened the theoretical system of the sex determination mechanism of bony fish. The gene expression and epigenetic characteristics of gender differences reveal the regulatory network of sexual differentiation, making tilapia a model organism for the study of vertebrate gender. The evolutionary conservation of the miRNA regulatory pathway in fish confirms its biological significance, while the interaction of genetics, hormones and epigenetics explains the environmental adaptability mechanisms (such as temperature-dependent sex plasticity), providing a new direction for the study of developmental regulation.

In the field of aquaculture, scientific research has confirmed that molecular marker technology can facilitate early gender identification, promote the breeding of unisexual populations, and effectively enhance the efficiency of aquaculture. The discovery of key regulatory genes provides precise targets for mark-assisted breeding and gene editing technologies such as CRISPR, significantly reducing the need for conventional hormone intervention and enhancing the ecological friendliness of aquaculture. The analysis of the gender reversal mechanism will revolutionize gender control technology, promote the optimization and upgrading of the breeding model, and achieve a dual increase in output and income.

Acknowledgments

I would like to thank Dr. Liu continuous support throughout the development of this study.”

Conflict of Interest Disclosure

The authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

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