case_images: PMC10847538_01
case_images: PMC10847538_02
case_images: Clinical and radiology manifestation in the current proband. (A) The proband presented bilateral ptosis and impaired flexion of bilateral knees. (B) Echocardiography demonstrated a normal heart function and structure. (C) Hip ultrasonography showed Graf type I structure on his left hip joint. (D) X-ray examination of hip joint and knee joint showed that there was no definite abnormality in anterior-posterior view, while the lateral view demonstrated an over-extensive positive of knee joint. (E) The joint MRI presented a normal signaling in muscles, bones and ligaments associated to his knee joints while it still presented an over-extensive position, and the tail vertebras were normal. (F) The cerebral MRI revealed a normal structure and signaling both in T1 and T2.
case_images: fneur-15-1343025-g002.jpg
case_images: PMC10847538_02_fneur-15-1343025-g002.jpg
case_images: fig2
case_images: The echocardiography demonstrated a normal heart function and structure (Figure 2B). The Hip ultrasonography showed a Graf type I structure on his left hip joint and a Graf type IIa structure on his right hip joint (Figure 2C). In contrast, the lateral view demonstrated an over-extensive positive of the knee joint (Figures 2D,D'). In addition, the joint MRI presented normal signaling in muscles, bones, and ligaments associated with his knee joints while it still presented an over-extensive position with a decreased volume of cartilage, indicating degradation of chondrocyte, while the tail vertebras were normal (Figures 2E,E'). MRI revealed a typical structure and signaling in T1 and T2 (Figures 2F,F'). Moreover, electromyography was involved, which presented a normal muscle response.
case_images: The ECEL1 molecular analysis. (A) The proband exhibited a compound heterozygous variant of ECEL1 (c.2152-15C>A and c.110_155del, p.F37Cfs*151). (B) The variant of ECEL1 c.110_155del had never reported in 1000G and ExAC, it has predicted protein damaging by PolyPhen-2 and SFIT, while only one report had been retrieved of the ECEL1 c.2152-15C>A variant. (C) Sanger sequence validation. (D) Protein structure predicted by AlphaFold (AF-O95672-F1), two topological domains and one transmembrane structure had been revealed with analyzed crystal structure. The variant of c.110_155del leads to the truncated protein locating in the substructure of transmembranous site.
case_images: fneur-15-1343025-g003.jpg
case_images: PMC10847538_02_fneur-15-1343025-g003.jpg
case_images: fig3
case_images: The Sanger validation demonstrated that the c.2152-15C>A allele was maternal inherited and the c.110_155del allele was paternal inherited (Figure 3A). The variant of ECEL1 c.110_155del had never reported in database (Figure 3B), while two cases reported the variant of ECEL1 c.110_155del. The Sanger sequencing had been presented in Figure 3C. The truncated protein lost the substructure of transmembranous site (Figure 3D).
case_images: PMC10847538_03