SYNE1, also known as spectrin repeat containing nuclear envelope protein 1. It is expressed in skeletal and smooth muscle, as well as peripheral blood lymphocytes, and localizes to the nuclear membrane. Mutations in the SYNE1 gene have been associated with several diseases, including autosomal recessive spinocerebellar ataxia type 8 (also referred to as autosomal recessive cerebellar ataxia type 1 or recessive ataxia of Beauce) and Emery-Dreifuss muscular dystrophy 4, autosomal dominant. The SYNE1 gene exhibits ubiquitous expression across various tissues, including the ovary and bone marrow. The molecular weight of the SYNE1 protein can vary depending on the specific isoform. For example, the full-length nesprin-1 isoform, also known as nesprin-1 giant, has 8797 amino acids and a molecular weight of approximately 1000 kDa. Another isoform, nesprin-1α2, has a molecular weight of about 120 kDa (PMID: 27782104). The protein has other isoforms with molecular weights of 380 kDa, 167 kDa and 642 kDa respectively.