Y-Chromosome Bodies in Brain and Kidney: The Normal Variation and an Unexpected Finding in Sudden Infant Death Syndrome

The variation in the number of detectable Y-body like particles from brain and kidney was investigated in 223 males and 122 females. There was found to be a decreasing number in males with increasing age. The frequency of false negatives (≤ 10 per cent) in male brains was 1 per cent, in kidneys 5 per cent. The frequency of false positives (> 10 per cent) in female brains was 34 per cent, in kidneys 10 per cent. In brain tissue from boys where the cause of death was given as Sudden Infant Death Syndrome (SIDS) was found the highest number of fluorescent Y-body like particles, although not quite significant, and frequently more than one in each cell. The hypothesis is presented that some of these represent virus inclusion bodies and that the cause of SIDS may be virus encephalitis.