Whole-blood serotonin (5-HT) and plasma norepinephrine (NE) were studied
in 16 autistic children, 21 siblings of autistic children, and 53 parents
of autistic children. Both plasma NE and whole-blood 5-HT were negatively
correlated with vocabulary performance. Whole-blood 5- HT and plasma NE did
not differ between autistic children with or without histories of
self-injurious behavior or decreased pain sensitivity. Eighteen subjects
were hyperserotonemic (whole-blood 5-HT greater than 270 ng/ml). For these
subjects, plasma NE was significantly higher than for subjects without
hyperserotonemia. Seven of 10 families with one hyperserotonemic member had
two or more hyperserotonemic members. Observations of familiarity of
whole-blood 5- HT suggest that larger-scale and more focused study of
whole-blood 5-HT as a possible genetic marker may be productive.Abstract Teaser