SPASTIC PARAPARESIS ASSOCIATED WITH HUMAN T-LYMPHOTROPIC VIRUS TYPE-I- A CLINICAL, SEROLOGICAL, AND GENOMIC STUDY IN IRANIAN-BORN MASHHADIJEWS

The Mashhadi-Jewish community originating in Iran is a closed and ethn ically segregated population with a unique history and a high rate of intrafamilial marriage among its members. A high risk of infection by human T-lymphotropic virus type I (HTLV-I) and of adult T-cell leukemi a associated with such infection was found in this population. HTLV-I is also associated with a syndrome of progressive spastic paraparesis. We therefore evaluated the occurrence of HTLV-I infection and spastic paraparesis in Mashhadi-born Iranian Jews who immigrated to Israel. W e examined 83 Mashhadi-born subjects (52 women, 31 men; mean age, 61 /- 15.5 years) and 73 age-matched non-Mashhadi Iranian-born Jews. Bloo d samples were tested for HTLV-I antibodies by particle agglutination test. The polymerase chain reaction (PCR) was used to detect HTLV-I pr oviral DNA sequences from peripheral blood mononuclear cells. Fifteen Mashhadi-born Jews (18%) were both seropositive and PCR-positive for H TLV-I. Four HTLV-I-seronegative subjects were found to be positive for HTLV-I proviral DNA by PCR. Of the 19 HTLV-1-infected subjects (11 wo men, 8 men; mean age, 59 +/- 16 years), 13 (68%) had spastic parapares is of varying severity. There were no signs of myelopathy in the Mashh adi-born subjects who were negative for HTLV-I proviral DNA by PCR. No ne of the non-Mashhadi Iranian Jews was seropositive or PCR-positive f or HTLV-I proviral DNA, or had clinical signs of spastic paraparesis. Our study indicates a high incidence of HTLV-I infection and spastic p araparesis in Mashhadi-born Iranian Jews. Possible transmission mechan isms may be related to a high rate of infection in this closed communi ty, or to a genetically transmitted virus in a susceptible high-inbred population.