Fktn, encoding fukutin, is a ribitol 5-phosphate transferase involved in the glycosylation of α-dystroglycan [2]. The glycosylation process is crucial as it impacts the function of α-dystroglycan, which is related to muscle and cardiac functions. Mutations in Fktn can lead to dystroglycanopathy, a group of syndromes with a broad clinical spectrum including dilated cardiomyopathy and muscular dystrophy [2].

In a study of Chinese patients with dystroglycanopathy, mutations in FKTN were among the identified mutations in this group of patients, although less prevalent compared to some other genes like FKRP [1]. In another case report, compound heterozygous mutations in FKTN led to a loss of fully glycosylated α-dystroglycan, resulting in cardiomyopathy and end-stage heart failure at a young age [2]. Also, in a child with congenital muscular dystrophy, compound heterozygous variants of the FKTN gene were found, suggesting these variants underlay the disease [3]. Prenatal whole-exome sequencing detected compound variants in FKTN in fetuses with congenital hydrocephalus, demonstrating the genetic heterogeneity in such patients [4].

In conclusion, Fktn is essential for the glycosylation of α-dystroglycan, and its malfunction due to mutations can lead to various disorders, mainly muscular dystrophy and cardiomyopathy. The study of Fktn through case reports and patient-based genetic analysis helps to understand the molecular mechanisms underlying these diseases, providing insights for potential diagnosis and treatment strategies.