X/autosome translocation in three generations ascertained through an infant with trisomy 16p due to failure of spreading of X-inactivation

✍ Scribed by Preis, Wolfgang; Barbi, Gotthold; Liptay, Susanne; Kennerknecht, Ingo; Schwemmle, Sabine; Pohlandt, Frank

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 20 KB
• Volume: 61
• Category: Article
• ISSN: 0148-7299
• DOI: 10.1002/(sici)1096-8628(19960111)61:2<117::aid-ajmg2>3.0.co;2-u

✦ Synopsis

We report on a reciprocal translocation t(X;16)(q28;p12) detected in a newborn girl with clinical manifestations of partial trisomy 16p. A balanced translocation was found in the mother and in the maternal grandmother. Replication studies on lymphocytes and fibroblasts showed nonrandom X-inactivation in both the patient and her mother. In the mother, the derivative X (der(X)) was active, whereas the normal X was late replicating. In contrast, in the patient the der(X) was late replicating, and there was no spreading of X-inactivation onto the autosomal segment, thus giving an explanation for the full clinical picture of partial trisomy 16p.