Fig. 2

Synapsin I protein diagram and the distribution of the variants. The SYN1 gene encodes two isoforms, Ia and Ib. They have four former similar domains (A–D), and a distinctive C-terminus (domain E or F). The isoform of Synapsin Ia is longer and expressed higher than Synapsin Ib. The variants identified in previous studies and this study (marked as asterisk) are indicated with different colors denoting different mutation types, including 10 missense variants (in black color), 5 truncation variants (in red color), and 1 splicing variant (in blue color)