DiGeorge Syndrome/Velocardiofacial Syndrome: The Chromosome 22q11.2 Deletion Syndrome

Atypical attentional filtering of visual information in youth with chromosome 22q11.2 deletion syndrome as indexed by event-related potentials

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Attentional control measured in 22q youth and typically developing control group.

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Differences in attentional control indexed by N2pc and PD event-related potentials.

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22q youth exhibited sustained focus on distractor cues and reduced suppression.

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No relationships between attentional control and psychosis-proneness in 22q youth.

Background

Youth with chromosome 22q11.2 deletion syndrome (22q) face one of the highest genetic risk factors for the development of schizophrenia. Previous research suggests impairments in attentional control and potential interactions with elevated anxiety and reduced adaptive functioning may increase the risk for developing psychosis in this population. Here, we examined how variations in attentional control relate to the presence or severity of psychosis-proneness symptoms in these individuals.

Methods

To achieve this, we measured attentional control in youth (12–18 years) with 22q (N = 35) compared to a typically developing group (N = 45), using a flanker task (the Distractor Target task) while measuring neural activity with event-related potentials.

Results

Similar to previous findings observed in people with schizophrenia, greater attentional capture by, and reduced suppression of, non-target flanker stimuli characterized participants with 22q and was indexed by the N2pc (N2-posterior-contralateral) and P_D (distractor positivity) components. Although we observed no relationships between these components and measures of psychosis-proneness in youth with 22q, these individuals endorsed a relatively low incidence of positive symptoms overall.

Conclusions

Our results provide neural evidence of an attentional control impairment in youth with 22q that suggests these individuals experience sustained attentional focus on irrelevant information and reduced suppression of distracting stimuli in their environment. Impairments in attentional control might be a valid biomarker of the potential to develop attenuated positive symptoms or frank psychosis in high-risk individuals long before the age at which such symptoms typically arise. The evaluation of such a hypothesis, and the preventive potential for the putative biomarker, should be the focus of future studies.

Variability in Clinical and Anatomical Manifestation of Velocardiofacial Syndrome Presents Diagnostic and Policy Uncertainty

OBJECTIVE

This study examined the complexity and myriad clinical manifestations and expressions of velocardiofacial syndrome (VCFS). It aimed to determine if VCFS invariably met the three disability criteria for the Compassionate Allowance List (CAL) program administered by the Social Security Administration (SSA).

METHODS

A systematic evaluative review of the literature found in 10 academic databases was completed. Inclusion criteria of the search terms yielded 1,383 initial manuscripts. Only 77 of articles met higher-level inclusion criteria of explicit statements reporting observed severity of symptoms and disability that this study used as evidence. The three SSA CAL criteria include duration, severity, and impact of employment. The analysis systematically reviewed papers with the objective of determining if they met one, two, or all three of the SSA CAL criteria. Results The first criteria for the CAL require a condition to last beyond 12 months. From the 77 articles that met inclusion criteria, a total of 21 articles reported explicit statements that evidenced symptoms that were limited to the first criteria only. The second CAL criteria required that a condition also has negative impact on quality of life or death. Forty-nine articles demonstrated the first and second criteria, duration ≥12 months plus a negative impact on quality of life or death. The third criteria required that the condition prevents substantial gainful employment as well as duration ≥12 months plus a negative impact on quality of life or death. A total of seven articles reported all three criteria.

CONCLUSIONS

The variability of symptoms related to VCFS makes it impossible to assert that all cases will meet the criteria for disability entitlements.

Application of array-comparative genomic hybridization in tetralogy of Fallot

To explore the underlying pathogenesis and provide references for genetic counseling and prenatal gene diagnosis, we analyzed the chromosome karyotypes and genome-wide copy number variations (CNVs) in 86 patients with tetralogy of Fallot (TOF) by G-banding karyotype analysis and array-comparative genomic hybridization (aCGH), respectively. And then quantitative polymerase chain reaction was used to validate these candidate CNVs. Based on their different properties, CNVs were categorized into benign CNVs, suspiciously pathogenic CNVs, and indefinite CNVs. Data analysis was based on public databases such as UCSC, DECIPHER, DGV, ISCA, and OMIM.The karyotype was normal in all the 86 patients with TOF. CNVs were detected in 11 patients by aCGH and quantitative polymerase chain reaction. Patient no. 0001, 0010, and 0029 had 2.52-Mb deletion in the chromosome 22q11.21 region; patient no. 0008 had both 595- and 428-kb duplications, respectively, in 12p12.3p12.2 and 14q23.2q23.3 regions; patient no. 0009 had 1.46-Mb duplication in the 1q21.1q21.2 region; patient no. 0016 had 513-kb duplication in the 1q42.13 region; patient no. 0024 had 292-kb duplication in the 16q11.2 region; patient no. 0026 had 270-kb duplication in the 16q24.1 region; patient no. 0028 had 222-kb deletion in the 7q31.1 region; patient no. 0033 had 1.73-Mb duplication in the 17q12 region; and patient no. 0061 had 5.79-Mb deletion in the 1p36.33p36.31 region.aCGH can accurately detect CNVs in the patients with TOF. This is conducive to genetic counseling and prenatal diagnosis for TOF and provides a new clue and theoretical basis for exploring the pathogenesis of congenital heart disease.

Hypoparathyroidism: clinical features, skeletal microstructure and parathyroid hormone replacement

OBJECTIVE

Hypoparathyroidism is a disorder in which parathyroid hormone is deficient in the circulation due most often to immunological destruction of the parathyroids or to their surgical removal. The objective of this work was to define the abnormalities in skeletal microstructure as well as to establish the potential efficacy of PTH(1-84) replacement in this disorder.

SUBJECTS AND METHODS

Standard histomorphometric and microCT analyses were performed on iliac crest bone biopsies obtained from patients with hypoparathyroidism. Participants were treated with PTH(1-84) for two years.

RESULTS

Bone density was increased and skeletal features reflected the low turnover state with greater BV/TV, Tb. Wi and Ct. Wi as well as suppressed MS and BFR/BS as compared to controls. With PTH(1-84), bone turnover and bone mineral density increased in the lumbar spine. Requirements for calcium and vitamin D fell while serum and urinary calcium concentrations did not change.

CONCLUSION

Abnormal microstructure of the skeleton in hypoparathyroidism reflects the absence of PTH. Replacement therapy with PTH has the potential to correct these abnormalities as well as to reduce the requirements for calcium and vitamin D.