[Pathological anatomy of monogenic syndromes of multiple congenital developmental defects].

Morphological study, with no selection, is performed of 1106 stillborns and children died before one year of age with congenital malformations (CM), 536 (46.9 +/- 1.5%) among them having multiple CM. Syndrome diagnosis is made in 44.1 +/- 2.1% cases: in 26.9 +/- 1.9% among them these were syndromes of chromosomal and in 17.9 +/- 1.7% syndromes of non-chromosomal etiology. Monogenic hereditary forms among non-chromosomal syndromes were in 42.1 +/- 4.8%. Comparative analysis of frequency and types of CM of various systems in monogenic and chromosomal syndromes and unclassified CM showed that the monogenic syndromes by their phenotypic manifestations are close to the chromosomal syndromes. The uniformity of alterations of certain morphological structures in these syndromes appear to be the consequence of common ways of realisation of both mutant genes in monogenic syndromes and their imbalance in chromosomal syndromes.