Clinico-genetic analysis of 21 personal observations and review of the literature confirmed the existence of a wide phenotypic spectrum of Dubowitz syndrome. It is shown that in spite of marked microcephaly, severe mental deficiency is rare in Dubowitz syndrome and about half of the patients are mentally normal. A "new" clinical subtype is defined, which also includes anorectal anomalies and premature craniosynostosis. All three families with this form are natives of a small area of Byelorussia, suggesting an autosomal or X-linked recessive mode of inheritance of this subtype. The data obtained confirm autosomal recessive inheritance of Dubowitz syndrome.