22q13 deletion syndrome

Abstract

We have recently collected clinical information on 37 individuals with deletion of 22q13 and compared the features of these individuals with 24 previously reported cases. The features most frequently associated with this deletion are global developmental delay, generalized hypotonia, absent or severely delayed speech, and normal to advanced growth. Minor anomalies include dolicocephaly, abnormal ears, ptosis, dysplastic toenails, and relatively large hands. As with many terminal deletions involving pale G-band regions, the deletion can be extremely subtle and can go undetected on routine cytogenetic analysis. In fact, 32% of the individuals in our study had previous chromosome analyses that failed to detect the deletion. Eight of 37 individuals had deletion of 22q13 secondary to an unbalanced chromosome translocation. In the newborn, this deletion should be considered in cases of hypotonia for which other common causes have been excluded. In the older child, this syndrome should be suspected in individuals with normal growth, profound developmental delay, absent or delayed speech, and minor dysmorphic features. We recommend high-resolution chromosome analysis and fluorescence in situ hybridization studies, or molecular analysis to exclude this diagnosis.

Phelan–McDermid Syndrome and SHANK3: Implications for Treatment

“…ANK=ankyrin repeat domain; SH3=Src homology 3; PDZ=PSD-95-discs large-zone occludens-1; Pro-rich=proline-rich region; SAM=sterile alpha motif [8]. Studies to date report a wide range of ASD prevalence in PMS, suggesting rates up to 94 % [8, [44][45][46]. The discrepancies in the rates of ASD in PMS are likely due to inconsistent evaluation methods across studies and the inherent challenges in diagnosing ASD in individuals with severe ID and developmental delay.…”

“…Developmental delays may not be apparent in the first 12 months of life, but a common presenting symptom in infants is hypotonia, which can also contribute to poor feeding, weak cry, and poor head control [43,51]. Low muscle tone and coordination deficits also contribute to significant delays in achieving major motor milestones like rolling over, crawling, and walking [46,[52][53][54]. The degree to which gross and fine motor coordination is affected in PMS can vary by location and severity, but gait is almost uniformly affected [10,43], with some reports of inability to ambulate [10,51].…”

“…The reported prevalence of seizures in PMS ranges up to approximately 40 % [10,26,45,46,52,54,56,[58][59][60][61], but most case series are retrospective relying on parent report or medical record review instead of prospective analysis of electroencephalographic results. Brain magnetic resonance imaging is typically recommended because structural brain abnormalities have been reported in approximately 75 % of patients described in the literature [10,26,45,55,62].…”

“…The gastrointestinal system is also commonly involved in the clinical symptomatology of PMS, which includes gastoesophageal reflux disease, constipation, diarrhea, and cyclic vomiting [10,43,46,52,54]. Patients with PMS have a higher prevalence (~25 %) of congenital heart defects.…”

Síndrome de Phelan McDermid: descripción de cinco pacientes e informe del primer caso descripto en gemelas siamesas

“…2,3,7 El diagnóstico se realiza mediante estudio citogenético, hibridación in situ fluorescente (FISH), hibridación genómica comparada (HGC), MLPA (multiplex ligation dependent probe amplification) o microarrays.…”