Ocular Anomalies Associated with Interstitial Deletion of Chromosome 2q31: Case Report and Review

Genotype-phenotype correlation in eight new patients with a deletion encompassing 2q31.1

Microdeletions of the 2q31.1 region are rare. We present the clinical and molecular findings of eight previously unreported patients with overlapping deletions in 2q31.1. The patients have a variable clinical phenotype and present with developmental delay (7/8), growth retardation (5/8), seizures (2/8) and a craniofacial dysmorphism consisting of microcephaly (4/8), short palpebral fissures (7/8), broad eyebrows with lateral flare (7/8), low-set ears with thickened helices and lobules (5/8), and micrognathia (6/8). Additional congenital anomalies were noted, including limb abnormalities (8/8), heart defects (3/8), genital anomalies (3/8), and craniosynostosis (1/8). Six of these microdeletions, ranging in size from 1.24 to 8.35 Mb, were identified by array CGH, one larger deletion (19.7 Mb) was detected by conventional karyotyping and further characterized by array CGH analysis. The smallest region of overlap in all eight patients spans at most 88 kb and includes only the WIPF1 gene. This gene codes for the WAS/WASL interacting protein family member 1. The patients described here do not present with clinical signs of the Wiskott-Aldrich syndrome and the deletion of this single gene does not allow explaining the phenotype in our patients. It is likely that the deletion of different but overlapping sets of genes from 2q31 is responsible for the clinical variability in these patients. To further dissect the complex phenotype associated with deletions in 2q31, additional patients with overlapping phenotypes should be examined with array CGH. This should help to link particular phenotypes to specific genes, and add to our understanding of the underlying developmental processes.

Ectodermal dysplasia-like syndrome with mental retardation due to contiguous gene deletion: further clinical and molecular delineation of del(2q32) syndrome

We report on a patient with an interstitial deletion of the long arm of chromosome 2 at 2q31.2q33.2. She had prenatal and postnatal growth retardation, microcephaly, facial dysmorphism, cleft palate, camptodactyly, bilateral talipes equinovarus, severe intellectual disability, and ectodermal anomalies. She showed thin, atrophic skin, sparse, brittle, slowly growing hair, oligodontia with abnormally shaped teeth, normal sweating, and normal fingernails, consistent with a diagnosis of ectodermal dysplasia. Array CGH analysis (Agilent 44K) showed the deletion to span 26 Mb, between cytogenetic bands 2q31.2 and 2q33. The deletion leads to hemizygosity for the HOXD cluster and its regulatory elements, COL3A1/COL5A2, GTF3C3, CASP8, CASP10, and SABT2 could perhaps interfere with long range control of DLX1 and DLX2 expression. This girl confirms the existence of a clinically recognizable 2q32 microdeletion syndrome, as recently delineated by Van Buggenhout et al. and confirms a novel putative locus for ectodermal dysplasia on chromosome 2q31q33. We recommend considering cytogenetic and/or molecular screening for del(2q32) in patients with developmental disability and ectodermal dysplasia-like phenotype, including thin skin, oligodontia, dysplastic teeth, and sparse hair.

Blepharophimosis and mental retardation (BMR) phenotypes caused by chromosomal rearrangements: description in a boy with partial trisomy 10q and monosomy 4q and review of the literature

Blepharophimosis is a rare congenital anomaly of the palpebral fissure which is often associated with mental retardation and additional malformations. We report on a boy with blepharophimosis, ptosis and severe mental retardation carrying an unbalanced 4;10 translocation with terminal duplication of 10q [dup(10)(q25.1-->qter)] and monosomy of a small terminal segment of chromosome 4q [del(4)(34.3-->qter)]. Detailed clinical examination and review of the literature showed that the phenotype of the patient was mainly determined by the dup(10q). This paper reviews the chromosomal aberrations associated with BMR (blepharophimosis mental retardation) phenotypes. Searching different databases and reviewing the literature revealed 14 microscopically visible aberrations (among them UPD(14)pat) and two submicroscopic rearrangements causing blepharophimosis and mental retardation (BMR) syndrome. Some of these rearrangements-like the terminal dup(10q) identified in our patient or interstitial del(2q)-are associated with clearly defined phenotypes and can be well distinguished from each other on basis of clinical examination. This paper should assist clinicians and cytogeneticists when evaluating patients with BMR syndrome.