A child with deletion (14)(q24.3q32.13) and auditory neuropathy

An interstitial deletion in the middle and distal part of chromosome 14 is a rare chromosomal abnormality characterized by a wide spectrum of phenotypic manifestations. We present a patient with a nearly 20 Mb interstitial deletion of chromosome 14q24.3q32.13 determined by FISH, that is associated with minor dysmorphic features, developmental delay, absent speech and auditory neuropathy. The deleted region contains 130 known genes, among them 48 with reported function or association with human disease. The patient's phenotype is compared with interstitial deletions of the distal part of chromosome 14 reported previously. We hypothesize, that there is (are) a gene (genes) in the 14q32.11-q32.13 that is (are) important for the hearing process and for which haploinsufficiency can cause auditory neuropathy. Several genes in the region, among them calmodulin, chromogranin A, the goosecoid and FOXN3, can contribute to the observed phenotype. Detailed mapping in additional patients with 14q32 deletions and hearing loss could further define the candidate region.     

Interstitial deletion of 5q33.3q35.1 in a girl with mild mental retardation

Constitutional interstitial deletions of 5q are uncommon. The corresponding phenotype is not well defined. But severe mental retardation seems to be a consistent manifestation. We describe a 4-year-old girl with a de novo deletion of 5q33.3q35.1 presenting only with mild psychomotor delay, minor facial anomalies, and seizures.     

A 3 Mb deletion in 14q12 causes severe mental retardation, mild facial dysmorphisms and Rett-like features

The present report describes a 7-year-old girl with a de novo 3 Mb interstitial deletion of chromosome 14q12, identified by oligo array-CGH. The region is gene poor and contains only five genes two of them, FOXG1B and PRKD1 being deleted also in a previously reported case with a very similar phenotype. Both patients present prominent metopic suture, epicanthic folds, bulbous nasal tip, tented upper lip, everted lower lip and large ears and a clinical course like Rett syndrome, including normal perinatal period, postnatal microcephaly, seizures, and severe mental retardation. FOXG1B (forkhead box G1B) is a very intriguing candidate gene since it is known to promote neuronal progenitor proliferation and to suppress premature neurogenesis and its disruption is reported in a patient with postnatal microcephaly, corpus callosum agenesis, seizures, and severe mental retardation.     

A 580 kb microdeletion in 17q21.32 associated with mental retardation, microcephaly, cleft palate, and cardiac malformation

We report on a young boy carrying a de novo 580 kb deletion in the 17q21.32 chromosomal band detected by array-CGH. He had multiple malformations including cardiac abnormalities, cleft palate, mental retardation, microcephaly, pronounced metopic suture and other minor facial dysmorphic features. This is the first case reported in the literature with such a small deletion in 17q21.32. This region includes 15 genes.     

Fragile (X)(q27) sites in a pedigree with female carriers showing mild to severe mental retardation.

A pedigree showing the fragile site at Xq27 in a severely retarded female and in other less retarded carriers is described. Two of the four moderately retarded males with the fra(X)(q27) show macro-orchidism, and a variety of other features usually used to support the effects of the fra(X)(q27) are also inconsistent. A second fragile site at (10)(q23) is also present and in the two oldest females its frequency is not decreased, whereas the fra(x)(q27) is not detectable in these females although probably present. It is concluded that pedigrees showing mentally retarded females and probable X linkage should be included in studies of the fra(X)(q27).     

Terminal deletion (14)(q32.3): a new case.

A mildly dysmorphic, 2 year old girl with mental retardation was found to have a small de novo terminal deletion of the long arm of chromosome 14, del(14)(q32.3). She was found to have features in common with two previous terminal deletion cases and particularly with the well documented ring 14 syndrome, although seizures, a characteristic feature of ring 14, were notably absent.     

Phenotypic manifestation in a child with 46,X,der(X)t(X;1)(q24;q31.1)

We report on a 5-year-old girl with multiple congenital anomalies, developmental delay, and a de novo unbalanced translocation between chromosomes X and 1[46,X,der(X)-t(X;1)(q24;q31.1)] resulting in partial trisomy 1q and partial monosomy Xq. The karyotype shows inactivation of the abnormal X chromosome. The translocated portion of 1q remains active in the tissues studied. This is the third case report with partial trisomy 1q and partial monosomy Xq. However, it is the first with specific breakpoints at 1q31.1 and Xq24.     

Interstitial deletion in 3q in a patient with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) and microcephaly, mild mental retardation and growth delay: clinical report and review of the literature

We present a boy with blepharophimosis, ptosis, epicanthus inversus, microcephaly, mild mental retardation, and growth delay. Chromosomal analysis revealed a male karyotype with an interstitial deletion in the long arm of chromosome 3. DNA-analysis showed that the deletion is of maternal origin and encompasses the region between markers D3S1535 and D3S1593. The deletion contains not only the FOXL2 gene, but also the gene encoding ataxia-telangiectasia and Rad3-related protein (ATR). Mutations in FOXL2 have been shown to cause blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). ATR has been identified as a candidate gene for Seckel syndrome, an autosomal recessive syndrome that comprises growth retardation, microcephaly, and mental retardation. We hypothesize that our patient has a contiguous gene syndrome and that the non-BPES-associated abnormalities (microcephaly, mild mental retardation, and growth delay) are the result of the deletion of the maternal ATR gene. However, it has not yet been excluded that haploinsufficiency of some other gene in this region plays a role.     

Yq- in a child with livedo reticularis, snub nose, microcephaly, and profound mental retardation.

A child with terminal deletion of the long arm of the Y chromosome (Yq--) presented with marked livedo reticularis, snub nose, microcephaly, short stature, and other dysmorphic features. He was profoundly mentally retarded. Most of the patients with Yq- have been reported as having varying dysmorphic features, mental retardation, and short stature. This child, in addition to the above, has livedo reticularis and microcephaly. He was of normal birthweight and, therefore, does not come into the syndrome of microcephaly, snub nose, livedo reticularis, and low birthweight dwarfism. Further information on Yq- should be obtained to ascertain if consistent patterns of abnormalities exist.     

A 5.6-Mb deletion in 15q14 in a boy with speech and language disorder, cleft palate, epilepsy, a ventricular septal defect, mental retardation and developmental delay

We report a male patient with speech and language disorder, cleft palate, epilepsy, a ventricular septal defect, mental retardation and developmental delay. Characteristic facial features include low-set ears, a beak-like nose, a prominent nasal bridge, a long philtrum, a narrow forehead, a long face, a pointed chin and dental position abnormalities. Array-comparative genomic hybridization (CGH) analysis demonstrated the presence of a 5.6-Mb deletion in 15q14 (chromosome 15: 3,18,33,000-3,74,77,000bp). The present case provides the evidence that 15q14 deletion outside the region encompassing the CHRNA7 gene can cause generalized epilepsy, and a locus in 15q14 is associated with speech and language disorder.     

A child with multiple congenital anomalies and karyotype 46,XY,del(14)(q31q32.3): further delineation of chromosome 14 interstitial deletion syndrome

We report on an infant with a multiple congenital anomaly syndrome and severe developmental delay in association with a previously undescribed de novo interstitial deletion of chromosome 14 [karyotype: 46,XY,del(14) (q31q32.3)]. Comparison of the presented patient with previously reported cases of interstitial and terminal chromosome 14q deletions provides a group of patients monosomic for various overlapping portions of the distal half of chromosome 14q and suggests a limited similarity in phenotype among patients with common deleted 14q segments. All patients with distal 14q deletions were developmentally delayed, most were microcephalic and failed to thrive. Most of the patient's anomalies were limited to the face and head. Few major internal congenital anomalies were observed. These comparisons serve to further clarify possible associations of subchromosomal aberrations with specific phenotypes.     

A report of a child with a deletion (9)(q34.3): a recognisable phenotype?

We report a case of a male infant who presented with congenital anomalies and was found to have a de novo deletion in the terminal region of the long arm of chromosome 9. He died at the age of 17 weeks of cardiorespiratory failure owing to RSV positive bronchiolitis. A review of previously published reports documented one previous report of a patient with a deletion of (9)(q34.3) and multiple congenital anomalies. Comparison with the previously reported case suggests that the phenotype observed constitutes a clinically recognisable pattern of malformations.     

A novel 1.4 Mb de novo microdeletion of chromosome 1q21.3 in a child with microcephaly,dysmorphic features and mental retardation

A 2.5 years old girl presented with moderate mental retardation, microcephaly, arching eyebrows, low set ears, long eyelashes, persistent fetal pads and clinodactyly. About 1 Mb deletion in the chromosomal region 1q21.3 was identified using BAC array CGH analysis. The parental follow up FISH analysis was normal. Further study of the deletion using a 244K oligo-array of Agilent Technologies Inc., Santa Clara, CA, USA defined the deleted region to span about 1.4 Mb with approximate genomic location chr1:152,511,593-153,993,103 (NCBI genome build 36). This is a novel deletion, not reported to-date. Larger proximal 1q deletions that were previously reported typically included microcephaly, mental retardation and multiple congenital anomalies. The deleted region reported here includes at least 30 coding genes. Among them of interest is a three-gene cluster of the ephrin gene family (EFNA1, EFNA3 and EFNA4). This is a group of receptor protein-tyrosine kinase type genes with presumed, but not completely characterized function in nervous system development.     

A consanguineous family with Hirschsprung disease, microcephaly, and mental retardation (Goldberg-Shprintzen syndrome)

Hirschsprung disease, mental retardation, microcephaly, and specific craniofacial dysmorphism were observed in three children from a large, consanguineous, Moroccan family. A fourth child showed similar clinical features, with the exception of Hirschsprung disease. The association of these abnormalities in these children represents the Goldberg-Shprintzen syndrome (OMIM 235730). Mutation scanning of genes potentially involved in Hirschsprung disease, RET, GDNF, EDN3, and EDNRB, showed a sequence variant, Ser305Asn, in exon 4 of the EDNRB gene in the index patient of this family. The Ser305Asn substitution present in two of the four patients and four healthy relatives and absent in one of the remaining two patients illustrates the difficulties in interpreting the presence of mutations in families with Hirschsprung disease. It is unlikely that the EDNRB variant contributes to the phenotype. This consanguineous family might be useful for the identification of a Goldberg-Shprintzen locus.     

A 2-Mb critical region implicated in the microcephaly associated with terminal 1q deletion syndrome

Patients with distal deletions of chromosome 1q have a recognizable syndrome that includes microcephaly, hypoplasia or agenesis of the corpus callosum, and psychomotor retardation. Although these symptoms have been attributed to deletions of 1q42-1q44, the minimal chromosomal region involved has not been identified. Using microsatellite and single nucleotide polymorphism (SNP) markers, we have mapped the deleted regions in seven patients with terminal deletions of chromosome 1q to define a 2.0-Mb microcephaly critical region including the 1q43-1q44 boundary and no more than 11 genes.     

Mild mental retardation in a child with a de novo interstitial deletion of 15q21.2q22.1: a comparison with previously described cases

We report on a child with mild mental retardation, hypotelorism, blepharophimosis, face slight asymmetry and partial hypoplasia of corpus callosum, with an interstitial deletion of a chromosome 15. The deletion was molecularly characterized by array-CGH and FISH techniques. This rearrangement has a 7.18 Mb extension and maps to 15q21.2q22.1. To date, there have been only six individuals reported with a deletion of 15q21; in three cases, the rearrangement was characterized by molecular cytogenetic techniques. After a comparison with these three cases, it appeared that the deletion we found is one of the smallest and it overlaps the distal portion of the ones taken into account. Finally, we tried to delineate the genotype–phenotype correlation in patients with a deletion of 15q21.