Schizophrenia in an adult with 6p25 deletion syndrome

Abstract

Chromosomal deletions at 6p25-p24 are rare findings in patients with developmental delay. There is limited information about the adult phenotype. We present a 36-year-old patient with schizophrenia, mild mental retardation, progressive hearing deficits, and characteristic facial features. Ocular (Axenfeld-Rieger anomaly) abnormalities were diagnosed in infancy; vision, however, has remained unimpaired. There were no other major congenital anomalies. Brain imaging showed only minor changes. There was no family history of intellectual deficits or psychosis. Karyotyping revealed a 6p25 deletion, and detailed fluorescence in situ hybridization (FISH) analyses using 23 probes confirmed a 6.7 Mb 6p25-pter deletion. The breakpoint is near a possible 6p25-p24 locus for schizophrenia. Psychotic illness may be part of the neurodevelopmental abnormalities and long-term outcome of patients with 6p terminal deletions. Other similarly affected patients likely remain to be diagnosed in adult populations of schizophrenia and/or mental retardation.

Pre‐ and postnatal phenotype of 6p25 deletions involving the FOXC1 gene

“…Furthermore, brain MRI in Patient 4 at 28 months showed diffuse white-matter T2 high signal in the subcortical and periventricular regions. Similar neuroimaging findings have been reported in nine patients with 6p25 deletion syndrome [Chen et al, 2004;Garcia-Cazorla et al, 2004;Caluseriu et al, 2006;van der Knaap et al, 2006;Aldinger et al, 2009] and in three patients with FOXC1 point mutations [Aldinger et al, 2009]. Patient #4 had delayed ossification and bilateral flattening of the proximal femoral epiphyses.…”

Primary cellular meningeal defects cause neocortical dysplasia and dyslamination

“…Patients with ARS and the 6p25 deletion syndrome, which includes FOXC1 and other loci, can have psychiatric and neurologic symptoms43-47, although comprehensive brain imaging results are lacking. A recent study found human FOXC1 mutations cause abnormal cerebellar development and meningeal defects48.…”

Axenfeld-Rieger syndrome: new perspectives: Figure 1

“…In the latter pedigree, heterogeneity in phenotype was also reported, but the clinical severity increased in successive generations. Caluseriu et al described an adult with deletions at 6p25–p24 who had developmental delay, progressive hearing loss, epiphysial dysplasia and abnormal sella turcica, schizophrenia and features of ARS 25. Several reports have noted that ARS can occur in association with failure of the periumbilical skin to involute, resulting in a periumbilical ring or redundant tissue surrounding the umbilicus.…”