Correlation of trisomy 13 with atelencephalic aprosencephaly

Abstract

A rare phenotype-genotype correlation of atelencephalic aprosencephaly in a fetus with free trisomy 13 karyotype, obtained by pregnancy termination for holoprosencephaly during the 26th gestational week, is presented. Lack of cerebral hemispheres and presence of rudimentary diencephalon, brain stem and hypoplastic cerebellum were revealed. Agenesis of the eyeball, of the optic nerve and of the pyramids of the medulla oblongata was established. Skull and face examination found craniostenosis, microcephaly, cella turcica agenesis, cyclopia, cleft palate and nose agenesis.The correlation between the most common karyotype of trisomy 13 and the very rare brain abnormality atelencephalic aprosencephaly suggests that the study of parental karyotype is desirable to inform parents about its accidental and non-hereditary nature in a probable future pregnancy.