Inherited retinal diseases (IRD) are a group of genetic disorders with high genetic and clinical heterogeneity. Patients with IRD may have their clinical diagnosis confirmed by genetic testing. Over the past 30 years, rapid advances in molecular genetics have raised the disease-causing gene variant detection rate and the accuracy of genetic testing, which provide hope to patients. The genetic diagnosis of patients with IRD is complicated due to the overlapping clinical phenotypes, and the fact that different variants lead to different phenotypes and severity even of the same gene. It is very important to overall evaluate the clinical phenotype of patients, precisely select genetic testing methods, and reasonably define disease-causing genes and variants during genetic diagnosis, which can guide the patient's subsequent treatment and provide genetic counseling.
The human hereditary retinal degeneration is one of the main cause of irreversible blindness in the world. the mechanisms leading to retinal photoreceptor degeneration are not entirely clear. However, microglia acting as innate immune monitors are found to be activated early in retinal degeneration in many retinitis pigmentosa animal models. These activated microglia are involved in phagocyte rod cell fragments of degenerated retina, and also produce high levels of cytotoxic substances such as pro-inflammatory cytokines and chemokines, which aggravate the death of adjacent healthy photoreceptor cells. It suggests that microglia activation plays an important role in photoreceptor degeneration. At the same time, a series of studies have confirmed that some drugs can prevent or reduce neuronal death and slow the occurrence and progression of retinal degeneration by interfering with abnormal activation of microglia. It is expected to be a new choice for the treatment of hereditary retinal degeneration.