A girl fulfilling four/five of six inclusion criteria and eight/nine of 11
supportive criteria for atypical Rett syndrome had a cytogenetic deletion o
f chromosome 3p, del(3) (pter-->3p25.1 similar to 25.2). The deletion was s
ituated on the maternally derived chromosome and by molecular analysis the
deletion breakpoint was shown to be between DNA markers D3S3589 and D3S1263
.