Relation between histocompatible antigen (human leukocyte antigen hla class 1 ) and sensorineural hearing loss of the aging process

The diminution of hearing with aging process is always sensorineural. It isthe auditory manifestation of a biological process involving all the tissues of thebody. Both sexes can be affected but the true sex incidence has not been reliablyestablished. The speed of onset of degenerative changes in the ear is determinedby genetic factors, physical stress and noise exposure during a normal life span.The onset of presbycusis is earlier in the urban population than of the ruralpopulation.An interesting question is why some people develop sensorinerual hearing losswith aging and others do not, the explanation could be related to their immunitysystem. Because HLA is a genetic marker of the immunity system, weinvestigated the patients of SNHL with aging process and normally hearing senilepersons by tissue typing HLA class I aiming to discover a relation between HLAand the disease.HLA system is known to have an association with certain disease states.Several hypothesis have been advanced to explain this relation. The first holds thatHLA antigens are merely markers for immune response or suppressive genes. Thesecond suggests that HLA antigens act as receptors for etiologic agents. The thirdis that molecular mimicry. The last is that the expression of class II on the surfaceof the cells that do not normally express it , is responsible for disease.