Familial 14.5 Mb interstitial deletion 13q21.1-13q21.33: clinical and array-CGH study of a benign phenotype in a three-generation family.
We report on the clinical and cytogenetic findings as well as the array-based characterization of an interstitial familial 13q21 deletion initially recognized by standard karyotyping. Although 13q deletions are known to imply a wide variability of clinical consequences, the deletion carriers of the familial deletion in three generations did not reveal a relevant phenotype. The breakpoints and the deletion size in all three carrier individuals were determined by molecular karyotyping confirming a large 14.5 Mb deletion encompassing the 13q21.1-13q21.33 region identical in all three carriers. Gene paucity and the lack of dosage-sensitive genes in the delineated region might explain the apparently innocuous nature of this chromosomal anomaly. The example of this family presents evidence for describing the chromosomal region 13q21.1-13q21.33 as a large euchromatic variant or benign copy number variation without phenotypic consequences. Our data underline the importance of a phenogenetic approach combining clinical and laboratory evidence in the interpretation of segmental chromosomal anomalies especially in genetic counseling related to prenatal diagnosis.
Filges
Isabel
I
Division of Medical Genetics, Department of Biomedicine, University Children's Hospital, Basel, Switzerland. isabel.filges@ukbb.ch
Röthlisberger
Benno
B
Noppen
Christoph
C
Boesch
Nemya
N
Wenzel
Friedel
F
Necker
Judith
J
Binkert
Franz
F
Huber
Andreas R
AR
Heinimann
Karl
K
Miny
Peter
P
D002675:Child, Preschool; D002872:Chromosome Deletion; D025063:Chromosome Disorders; D002882:Chromosomes, Human, Pair 13; D055028:Comparative Genomic Hybridization; D005192:Family Health; D018628:Gene Dosage; D006801:Humans; D007621:Karyotyping; D008297:Male; D010375:Pedigree; D010641:Phenotype