Trisomy 10p: Report of an unusual mechanism of formation and critical evaluation of the clinical phenotype

✍ Scribed by Clement, Susan J.; Leppig, Kathleen A.; Jarvik, Gail P.; Kapur, Raj P.; Norwood, Thomas H.

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 748 KB
• Volume: 65
• Category: Article
• ISSN: 0148-7299
• DOI: 10.1002/(sici)1096-8628(19961028)65:3<197::aid-ajmg5>3.0.co;2-n

✦ Synopsis

A de novo tandem inverted duplication of lop was diagnosed in a 17-week fetus. The appearance of GTG banded preparations and the results of fluorescence in situ hybridization (FISH) studies are consistent with duplication of the entire arm, including the telomere. The FISH studies also demonstrated the presence of chromosome 10 alphoid repeats at the junction between the inverted segment and the long arm, consistent with the presence of the entire long arm of the abnormal chromosome. Therefore, this is a case of pure trisomy lop without an associated deficiency of any other chromosome segment. A comparison of the phenotype associated with pure trisomy lop and trisomy associated with a duplicatioddeficiency state documented a higher frequency (of borderline significance) of clubfoot and high-archedhleft palate in the cases of pure trisomy. The frequency of palatal anomalies was observed to be significantly higher in the cases where the breakpoint of the trisomic segment is in the most proximal band (1Opll). However, other clinical manifestations were observed inconsistently, even in the cases with pure, nearly complete trisomy lop. Therefore, a clearly defined trisomy lop clinical syndrome could not be documented in this study.