Frequency of Genetic Transmission of Sporadic Retinoblastoma

Abstract

The inheritability of retinoblastoma is a matter of practical concern to the patient and to the physician. In many cases, transmission follows the law of simple Mendelian dominance, and approximately 50% of the offspring of an affected person may be expected to have the disease. In the sporadic cases, that is, in cases of retinoblastoma which appear to occur without preexisting retinoblastoma in the family, the manner of transmission is not so obvious. Yet this information is essential to advise these persons concerning the chances of their offspring having the disease. This information can be obtained only by analyzing the records of patients with sporadic cases who have had children. Such is the aim of this study. Literature regarding the offspring of patients with carefully documented sporadic cases has been scanty. Hemmes¹reported in 1931 four patients with sporadic retinoblastoma with a total of nine offspring, none affected with