Normal and aberrant splicing of LMNA

The LMNA gene gives rise to at least three isoforms (lamin A, C, lamin AΔ10) as a result of normal alternative splicing, regulated by cis- and trans-acting regulatory factors, as well as the 50 and 30 untranslated regions of the gene. The two main isoforms, lamin A and C, are constitutive components of the fibrous nuclear lamina and have diverse physiological roles, ranging from mechanical nuclear membrane maintenance to gene regulation. The clinical spectrum of diseases (called 'laminopathies') caused by LMNA mutations is broad, including at least eight wellcharacterised phenotypes, some of which are confined to the skeletal muscles or skin, while others are multisystemic. This review discusses the different alternatively spliced isoforms of LMNA and the regulation of LMNA splicing, as well as the subgroup of mutations that affect splicing of LMNA pre-mRNA, and also seeks to bridge the mis-splicing of LMNA at transcript level and the resulting clinical phenotypes. Finally, we discuss the manipulation of LMNA splicing by splice-switching antisense oligonucleotides and its therapeutic potential for the treatment of some laminopathies.