[Subtelomeric deletion 9qter: definition of the syndrome and parental origin in 2 patients].
OBJECTIVE
Subtelomeric chromosome imbalances are increasingly known as a cause for mental retardation. New phenotypes associated with specific rearrangements are also being delineated, such as 9q microdeletion syndrome. Here we define the major phenotypic features and the parental origin of 9q deletion.


METHODS
We present 2 children with a phenotype that is characterized by mental retardation, distinctive facial features and congenital anomalies. Both patients showed a chromosome 9q subtelomeric deletion detected by MLPA (multiplex ligation-dependent probe amplification), and confirmed by FISH (fluorescent in situ hybridization). In order to delimit the size and the parental origin of 9q deletion, we performed microsatellite segregation analyses.


RESULTS
We identified 2 patients with a de novo terminal deletion of the chromosome region 9q34. The deleted region spanned less than 0.8 and 1.5 Mb, respectively, affecting in both cases the paternal chromosome.


CONCLUSIONS
9q34 deletion syndrome appears as a clinically recognizable phenotype characterised by moderate-severe mental retardation, hypotonia, flat face with hyperthelorism, synophrys, anteverted nares, carp-shaped mouth with protruding tongue and conotruncal heart defects. Most de novo deletions arise in the chromosomes of paternal origin.
Roselló
Mónica
M
Unidad de Genética y Diagnóstico Prenatal, Hospital Universitario La Fe, Avda. Campanar 21, 46009 Valencia, Spain. rosello_mpi@gva.es
Monfort
Sandra
S
Orellana
Carmen
C
Oltra
Silvestre
S
Martínez Garay
Isabel
I
Martínez
Francisco
F
D000328:Adult; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D005220:Fathers; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male; D021141:Nucleic Acid Amplification Techniques; D010641:Phenotype; D013577:Syndrome; D016615:Telomere / Q000235:genetics*