Duchenne muscular dystrophy (DMD) is a severe, progressive, and debilitating X-linked disorder characterized by muscle wasting. This condition precipitates difficulties with movement, eventually necessitating assisted ventilation, and often leads to premature death. The primary cause of DMD is mutations in the dystrophin muscular dystrophy (DMD) gene, which encodes the dystrophin protein. These mutations effectively eliminate the production of dystrophin protein in muscle tissues, instigating muscle atrophy and a myriad of complications ^[1]. The absence of dystrophin protein culminates in the disintegration of the dystrophin-associated protein complex (DAPC) within the muscle membrane. This disintegration disrupts the interaction between actin and the extracellular matrix, rendering muscles devoid of dystrophin more susceptible to damage. This susceptibility results in the progressive loss of muscle tissue and function, as well as the development of cardiomyopathy ^[2]. DMD-Q995* mice carry a c.2983C>T (p.Q995) mutation in the Dmd gene, which results in the production of a premature termination codon (PTC). In eukaryotes, the nonsense-mediated mRNA decay (NMD) pathway degrades mRNAs containing PTCs to reduce errors in gene expression. These abnormal mRNAs may encode harmful gain-of-function or dominant-negative proteins that can damage normal human physiological mechanisms. In DMD-Q995* mice, the mutation and the NMD pathway together result in the degradation of most Dmd transcripts. The remaining transcripts can only encode truncated dystrophin proteins that lack normal function, leading to the loss of dystrophin function ^[3-5]. This model, due to the lack of normal dystrophin expression, exhibits a series of muscle disease phenotypes similar to the clinical presentation of Duchenne muscular dystrophy (DMD), and can be used for research on DMD. Homozygous female mice and heterozygous males of this strain are viable and fertile.

Duchenne Muscular Dystrophy (DMD) is a severe, progressive, and disabling X-linked recessive genetic disorder characterized primarily by muscle atrophy. This disease leads to motor impairments, eventually requiring assisted ventilation, and often results in premature death. The primary cause of DMD is mutations in the DMD gene, which encodes the dystrophin protein. These mutations lead to a reduction or absence of dystrophin in muscle tissue, resulting in muscle atrophy and related complications ^[1]. The lack of dystrophin leads to the breakdown of the dystrophin-associated protein complex (DAPC) within the muscle membrane, disrupting the interaction between actin and the extracellular matrix, making the muscles more susceptible to damage. This susceptibility results in the gradual loss of muscle tissue and function, potentially leading to cardiomyopathy ^[2]. Researchers have identified thousands of different DMD gene mutations in patients with DMD. Deletion mutations account for approximately 60%–70%, while duplication mutations account for 5%–15%. These mutations are primarily concentrated in hotspot regions of the DMD gene, specifically between exons 45-55 (47%) and exons 3-9 (7%) ^[1]. Currently, gene therapy approaches for Duchenne Muscular Dystrophy (DMD) primarily include exon skipping and AAV supplementation, as well as emerging gene editing techniques like CRISPR. The exon skipping strategy involves using antisense oligonucleotide (ASO) drugs to bind to specific sequences of pre-mRNA, skipping the mutated exon and restoring the open reading frame (ORF) integrity, thus producing a truncated but partially functional dystrophin protein. Several ASO drugs targeting the DMD gene have been approved, such as Eteplirsen (targeting exon 51), Golodirsen (targeting exon 53), and Casimersen (targeting exon 45) developed by Sarepta, and Viltolarsen (targeting exon 53) developed by Nippon Shinyaku. Since most ASO and CRISPR-based gene editing therapies target the human DMD gene, humanizing mouse genes helps accelerate clinical applications for DMD therapies, considering the genetic differences between animals and humans. The B6-hDMD(E8-30) mouse is a humanized model of exons 8-30 of the Dmd gene, used for researching Duchenne Muscular Dystrophy. Homozygotes are viable and fertile. In addition, based on the independently developed TurboKnockout fusion BAC recombination technology, Cyagen provides other humanized models such as [hE49-53], [hE49-53, del E50], [hE44-45], [hE44-45, del E44], and [hE44-45, c.6438+2 T to A], covering most popular research areas and offering customized services based on different mutation needs.

Dmd is located on chromosome X of mice. Nuclease Technology was used to design sgRNA; Dmd knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Duchenne Muscular Dystrophy (DMD) is a severe, progressive, and disabling X-linked recessive genetic disorder characterized primarily by muscle atrophy. This disease leads to motor impairments, eventually requiring assisted ventilation, and often results in premature death. The primary cause of DMD is mutations in the DMD gene, which encodes the dystrophin protein. These mutations lead to a reduction or absence of dystrophin in muscle tissue, resulting in muscle atrophy and related complications ^[1]. The lack of dystrophin leads to the breakdown of the dystrophin-associated protein complex (DAPC) within the muscle membrane, disrupting the interaction between actin and the extracellular matrix, making the muscles more susceptible to damage. This susceptibility results in the gradual loss of muscle tissue and function, potentially leading to cardiomyopathy ^[2]. Researchers have identified thousands of different DMD gene mutations in patients with DMD. Deletion mutations account for approximately 60%–70%, while duplication mutations account for 5%–15%. These mutations are primarily concentrated in hotspot regions of the DMD gene, specifically between exons 45-55 (47%) and exons 3-9 (7%) ^[1]. Currently, gene therapy approaches for Duchenne Muscular Dystrophy (DMD) primarily include exon skipping and AAV supplementation, as well as emerging gene editing techniques like CRISPR. The exon skipping strategy involves using antisense oligonucleotide (ASO) drugs to bind to specific sequences of pre-mRNA, skipping the mutated exon and restoring the open reading frame (ORF) integrity, thus producing a truncated but partially functional dystrophin protein. Several ASO drugs targeting the DMD gene have been approved, such as Eteplirsen (targeting exon 51), Golodirsen (targeting exon 53), and Casimersen (targeting exon 45) developed by Sarepta, and Viltolarsen (targeting exon 53) developed by Nippon Shinyaku. Since most ASO and CRISPR-based gene editing therapies target the human DMD gene, humanizing mouse genes helps accelerate clinical applications for DMD therapies, considering the genetic differences between animals and humans. The B6-hDMD (E49-53) mouse is a humanized model of exons 49-53 of the Dmd gene, used for researching Duchenne Muscular Dystrophy. Homozygotes are viable and fertile. In addition, based on the independently developed TurboKnockout fusion BAC recombination technology, Cyagen provides other humanized models such as [hE49-53, del E50], [hE44-45], [hE44-45, del E44], [hE44-45, c.6438+2 T to A], and [hE8-30], covering most popular research areas and offering customized services based on different mutation needs.

Duchenne muscular dystrophy (DMD) is a severe, progressive, and debilitating X-linked disorder characterized by muscle wasting. This condition precipitates difficulties with movement, eventually necessitating assisted ventilation, and often leads to premature death. The primary cause of DMD is mutations in the dystrophin muscular dystrophy (DMD) gene, which encodes the dystrophin protein. These mutations effectively eliminate the production of dystrophin protein in muscle tissues, instigating muscle atrophy and a myriad of complications ^[1]. The absence of dystrophin protein culminates in the disintegration of the dystrophin-associated protein complex (DAPC) within the muscle membrane. This disintegration disrupts the interaction between actin and the extracellular matrix, rendering muscles devoid of dystrophin more susceptible to damage. This susceptibility results in the progressive loss of muscle tissue and function, as well as the development of cardiomyopathy ^[2]. Dmd-Q995X(DBA/2.B6) mice carry a c.2983C>T (p.Q995*) mutation in the Dmd gene, which introduces a premature termination codon (PTC) triggering nonsense-mediated mRNA decay (NMD) in eukaryotes. NMD degrades PTC-containing aberrant mRNAs to minimize gene expression errors, as these mRNAs may translate into harmful gain-of-function or dominant-negative proteins disrupting physiological mechanisms. The mutation combined with the murine NMD mechanism leads to the degradation of most Dmd transcripts in Dmd-Q995X(DBA/2.B6) mice, with remaining transcripts encoding nonfunctional truncated dystrophin, resulting in loss of dystrophin function ^[3-5]. Additionally, the inherent muscle regeneration dysfunction in the DBA/2 strain exacerbates myopathic phenotypes, including significant muscle atrophy, fibrosis, and pronounced muscle weakness, more accurately mimicking human DMD progression and severity ^[6]. This makes Dmd-Q995X(DBA/2.B6) mice, with their lack of functional dystrophin, ideal for modeling Duchenne muscular dystrophy (DMD) and evaluating therapeutic strategies.

Dmd is located on chromosome X of mice. SgRNA and ssDNA will be designed using Nuclease Technology; Dmd conditional knockout mice will be obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm will be collected for cryopreservation.

Duchenne Muscular Dystrophy (DMD) is a severe, progressive, and disabling X-linked recessive genetic disorder characterized primarily by muscle atrophy. This disease leads to motor impairments, eventually requiring assisted ventilation, and often results in premature death. The primary cause of DMD is mutations in the DMD gene, which encodes the dystrophin protein. These mutations lead to a reduction or absence of dystrophin in muscle tissue, resulting in muscle atrophy and related complications ^[1]. The lack of dystrophin leads to the breakdown of the dystrophin-associated protein complex (DAPC) within the muscle membrane, disrupting the interaction between actin and the extracellular matrix, making the muscles more susceptible to damage. This susceptibility results in the gradual loss of muscle tissue and function, potentially leading to cardiomyopathy ^[2]. Researchers have identified thousands of different DMD gene mutations in patients with DMD. Deletion mutations account for approximately 60%–70%, while duplication mutations account for 5%–15%. These mutations are primarily concentrated in hotspot regions of the DMD gene, specifically between exons 45-55 (47%) and exons 3-9 (7%) ^[1]. Currently, gene therapy approaches for Duchenne Muscular Dystrophy (DMD) primarily include exon skipping and AAV supplementation, as well as emerging gene editing techniques like CRISPR. The exon skipping strategy involves using antisense oligonucleotide (ASO) drugs to bind to specific sequences of pre-mRNA, skipping the mutated exon and restoring the open reading frame (ORF) integrity, thus producing a truncated but partially functional dystrophin protein. Several ASO drugs targeting the DMD gene have been approved, such as Eteplirsen (targeting exon 51), Golodirsen (targeting exon 53), and Casimersen (targeting exon 45) developed by Sarepta, and Viltolarsen (targeting exon 53) developed by Nippon Shinyaku. Since most ASO and CRISPR-based gene editing therapies target the human DMD gene, humanizing mouse genes helps accelerate clinical applications for DMD therapies, considering the genetic differences between animals and humans. The B6-hDMD (E49-53)*Del E50 mouse is a humanized model of the Dmd gene, in which the genomic sequences corresponding to exons 49–53 and their flanking regions in the mouse Dmd gene have been replaced with the corresponding human DMD gene sequences, followed by knock-out of exon 50 in the human DMD gene within the mouse genome. This model is suitable for research on Duchenne muscular dystrophy. In addition, based on the independently developed TurboKnockout fusion BAC recombination technology, Cyagen provides other humanized models such as [hE49-53], [hE44-45, c.6438+2 T to A], [hE8-30], covering most popular research areas and offering customized services based on different mutation needs.

Gsdmd is located on chromosome 15 of mice. Nuclease Technology was used to design sgRNA; Gsdmd knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Gsdmd is located on chromosome 15 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Gsdmd conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Gsdmd is located on chromosome 15 of mice. Nuclease Technology will be used to design sgRNA; Gsdmd knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.