RESUMEN
Retinitis pigmentosa (RP) is a large group of common hereditary eye diseases with highlyheterogeneous genetic background. Over forty genes with diverse functionalities are associated with RP and they include a set of ubiquitously expressed genes. These include five genes involved in the precursor messenger RNA( premRNA) splicing. Recent progress in disease gene identification for RP has established the involvement of pre-mRNA splicing as one important mechanism in the disease etiology and has shed light on the splicing process itself, a fundamental biological process. To this date, studies in this field have been focused on two major issues. First, how do the mutations of the adRP associated splicing factors (adRP-SF) affect the splicing function? Second, how do the mutations in these ubiquitously expressed genes lead to specific retinopathy? The two topics fit with the two continuous important steps of the disease pathogenesis. Recently, researchers have made a dramatic progress in the first topic. The identification of the SNRNP200 gene,the fifth adRP-SF and its relevant functional study has shown significance to the progress in the study of RP. Numerous investigations are also being carried out in addressing the second issue.Generation of a variety of models led to a better description of the pathological process of the disease. However, in respect to the key pathogenic mechanism,researchers are still puzzled with a number of confusing questions. In this commentary,the results from the latest investigations were summarized, and in particular,the difficulties in studying the molecular mechanism by which the pre-mRNA splicing deficiency causes RP were detailed.