<prompt> Retinitis pigmentosa is a feature of all except -Refsums diseaseHallervorden-Spatz diseaseNARPAbetalipoproteinemia  <response>: Retinitis pigmentosa has features of : 1.Refsums syndrome. It is characterised by retinitis pigmentosa, peripheral neuropathy and cerebellar ataxia. 2.Ushers syndrome. It includes retinitis pigmentosa and labyrinthine deafness. 3.Hallgrens syndrome. It comprises retinitis pigmentosa, vestibulocerebellar ataxia, congenital deafness and mental deficiency. 4. Other associated syndromes include Bussen- Koranzweig syndrome Abetalipoproteinaemia, Kearns-Sayer syndrome, Friedreichs ataxia, Bardet-Biedle syndrome, NARP neuropathy, ataxia, and retinitis pigmentosa, neuronal ceroid lipofuscinosis, olivopontocerebellar degeneration. Ref AK khurana 6e p 289 