De novo der(X)t(X;10)(q26;q21) with features of distal trisomy 10q: case report of paternal origin identified by late replication with BrdU and the human androgen receptor assay (HAR).
We describe an 11 year old girl with a de novo unbalanced t(X;10) that resulted in a deletion of Xq26-->Xqter and a trisomy of 10q21-->10qter. Her clinical features were of distal trisomy 10q, but she lacked the cardiovascular and renal malformations observed in duplications of 10q24-->10qter and had only moderate mental retardation. X inactivation was assessed on peripheral blood lymphocytes by late replication with BrdU (LR) and the human androgen receptor assay (HAR). By LR the der(X) was inactive without spreading to 10q21-->10qter in all cells. The HAR assay showed skewed methylation of the paternal allele (90%). The correlation of HAR and LR suggests that the der(X) was paternally inherited and is consistent with data from other de novo balanced and unbalanced X;autosome translocations detected in females. This is the first report of parental origin of a de novo trisomy 10q.
Garcia-Heras
J
J
Genetic Testing Center, Texas Department of Health, Denton 76202-2467, USA.
Martin
J A
JA
Witchel
S F
SF
Scacheri
P
P
D000015:Abnormalities, Multiple / Q000235:genetics; D001973:Bromodeoxyuridine; D002648:Child; D002872:Chromosome Deletion; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics*; D004261:DNA Replication; D002658:Developmental Disabilities / Q000235:genetics; D004303:Dosage Compensation, Genetic; D005260:Female; D006801:Humans; D011944:Receptors, Androgen / Q000235:genetics*; D014178:Translocation, Genetic; D014314:Trisomy / Q000235:genetics*; D014960:X Chromosome / Q000235:genetics*
D011944:Receptors, Androgen; D001973:Bromodeoxyuridine