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Published on: August 17, 2022

Intermediate interstitial deletion of chromosome 7q detected by first-trimester Down's syndrome screening

Mei-Leng Joy Cheong1, Ming-Song Tsai, Raul A Cortes

  • 1Fetal Treatment Center, University of California, San Francisco, CA 94143-0570, USA.

Fetal Diagnosis and Therapy
|October 9, 2008
PubMed

We report a case of prenatally diagnosed chromosome 7q intermediate interstitial deletion with the aid of first-trimester Down's syndrome (DS) screening. After detection of a significantly diminished maternal serum pregnancy-associated plasma protein A and correspondingly high DS risk, the pregnant woman underwent amniocentesis for fetal chromosomal analysis. Amniocytes revealed a 46,XY,del(7) (q21.2q31.1) karyotype and 21 weeks' sonography revealed fetal growth restriction, elevated nuchal fold thickness and cardiomegaly. After therapeutic induction at 22 weeks of gestation, a 310-gram male fetus was born with multiple gross abnormalities including hypertelorism, wide nasal bridge, low-set ears, cleft palate, prominent cheeks, prominent nuchal skin, simian crease and postaxial polydactyly. We review the associated prenatal screening findings, the sonographic profile and phenotypical features associated with chromosome 7q intermediate interstitial deletion.

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