Subtelomeric 6p deletion: clinical and array-CGH characterization in two patients.
We report on two patients with de novo subtelomeric terminal deletion of chromosome 6p. Patient 1 is an 8-month-old female born with normal growth parameters, typical facial features of 6pter deletion, bilateral corectopia, and protruding tongue. She has severe developmental delay, profound bilateral neurosensory deafness, poor visual contact, and hypsarrhythmia since the age of 6 months. Patient 2 is a 5-year-old male born with normal growth parameters and unilateral hip dysplasia; he has a characteristic facial phenotype, bilateral embryotoxon, and moderate mental retardation. Further characterization of the deletion, using high-resolution array comparative genomic hybridization (array-CGH; Agilent Human Genome kit 244 K), revealed that Patient 1 has a 8.1 Mb 6pter-6p24.3 deletion associated with a contiguous 5.8 Mb 6p24.3-6p24.1 duplication and Patient 2 a 5.7 Mb 6pter-6p25.1 deletion partially overlapping with that of Patient 1. Complementary FISH and array analysis showed that the inv del dup(6) in Patient 1 originated de novo. Our results demonstrate that simple rearrangements are often more complex than defined by standard techniques. We also discuss genotype-phenotype correlations including previously reported cases of deletion 6p.
Martinet
Danielle
D
Service of Medical Genetics, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. danielle.martinet@chuv.ch
Filges
Isabel
I
Besuchet Schmutz
Nathalie
N
Morris
Michael A
MA
Gaide
Anne-Claude
AC
Dahoun
Sophie
S
Bottani
Armand
A
Addor
Marie-Claude
MC
Antonarakis
Stylianos E
SE
Beckmann
Jacques S
JS
Béna
Frédérique
F
D000015:Abnormalities, Multiple / Q000235:genetics*; D002675:Child, Preschool; D002872:Chromosome Deletion; D007446:Chromosome Inversion; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D019465:Craniofacial Abnormalities / Q000235:genetics*; D002658:Developmental Disabilities / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype