PMC9911450_01
Photographs and lower limb muscle magnetic resonance imaging (MRI). (A, B) Photographs of the proband. Weakness of the eye and lip muscles. (C) The bilateral posterior thigh groups were markedly enlarged (star), especially of the lateral femoral muscle edges and central preservation (arrow). (D) Significant enlargement of the medial head of the gastrocnemius (arrow  ) and the anterior tibial muscles in both lower legs.
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F1
She was unable to grimace and puff her cheeks (Figures 1A, B). A significant enlargement of the medial head of the gastrocnemius and anterior tibial muscles was observed in both lower legs (Figures 1C, D).
Muscle biopsy (bar = 100 mum) and genotype results. (A) Hematoxylin and eosin (H&E) staining: the skeletal muscle tissue of the right anterior tibial muscle exhibited a slight myogenic damage. (B) Dysferlin staining: the myofiber membrane and cytoplasm were positive. (C) alpha-Sarcoglycan staining: the muscle fiber membrane was positive, with a uniform and continuous expression. (D-F) Sequencing of the COL6A3 gene in the patient (D), patient's mother (E), and patient's son (F). The variation c.6817-2(IVS27)A>G is present only in the patient.
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F2
Muscular pathological findings showed that the right tibial premuscle muscle fibers were clearly unequal in size, some of the muscle fibers were more clearly atrophied, some of the muscle fibers were mildly hypertrophied, a few muscle fiber nuclei were internally displaced, individual muscle clefts and nuclei aggregation were seen, muscle fiber degeneration and necrosis were not visible, and collagen VI immunostaining revealed a normal staining pattern (not shown; Figures 2A-C). Molecular studies, using the whole-genome sequencing technology, identified the heterozygous mutation c.6817-2(IVS27)A>G in the COL6A3 gene (Figures 2D-F).