Prenatal Diagnosis of a Partial Monosomy 7q11→q31 in a Fetus with Split Foot

Objective: A 27-year-old woman was referred to our laboratory for genetic counseling at 26 weeks of gestation due to abnormal ultrasound findings including intrauterine growth retardation, Dandy-Walker malformation and lower extremity anomalies. Methods: Chromosome analysis was performed on fetal blood sample obtained by cardiocentesis. Result: We observed an abnormal karyotype with a structural abnormality of the long arm of chromosome 7. Both parents’ chromosomes were normal; thus, the fetal karyotype designation was 46,XX, del(7)(pter→q11::q31→qter) de novo. Skin biopsy sample was taken to confirm the karyotype after therapeutic abortion was performed. The result was identical. Postmortem examination and autopsy showed facial dysmorphism, malformations of the lower extremities and central nervous system anomalies. Conclusion: 7q interstitial deletions cause a wide spectrum of congenital abnormalities and syndromes linked to the deleted segments. Our case had a rather wide chromosome region deleted and it is important, because prenatal diagnosis was performed. Thus, the family had the chance to evaluate the situation and decided to terminate the pregnancy after genetic counseling.

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