Figure 1. Family pedigree of RPGR ORF15 X-linked retinitis pigmentosa. Affected men from five known generations of the family suffer from severe retinitis
pigmentosa and are typically blind in their fourth decade. The disease-causing family mutation in RPGR ORF15 was identified with molecular genetic analysis of one affected male subject (fourth generation, third individual from
the left). A woman with the mutation examined at the age of 44 years had retinitis pigmentosa-like fundus abnormalities, tunnel
vision, night blindness, and subnormal visual acuity (third generation, sixth individual from the left). The proband is a
non-obligate carrier who at 16 years of age presented with a tapetal-like reflex in the light adapted state, but at reexamination
at 22 years of age showed marked attenuation of the tapetal-like reflex in the light adapted state and reappearance of the
tapetal-like reflex with prolonged dark adaptation.