Mutations in WDR62, encoding a centrosomal and nuclear protein, in Indian primary microcephaly families with cortical malformations

Primary microcephaly is an autosomal recessive disorder characterized by smaller than normal brain size and mental retardation. It is genetically heterogeneous with seven loci: MCPH1-MCPH7. We have previously reported genetic analysis of 35 families, including the identification of the MCPH7 gene STIL. Of the 35 families, three families showed linkage to the MCPH2 locus. Recent whole-exome sequencing studies have shown that the WDR62 gene, located in the MCPH2 candidate region, is mutated in patients with severe brain malformations. We therefore sequenced the WDR62 gene in our MCPH2 families and identified two novel homozygous protein truncating mutations in two families. Affected individuals in the two families had pachygyria, microlissencephaly, band heterotopias, gyral thickening, and dysplastic cortex. Using immunofluorescence study, we showed that, as with other MCPH proteins, WDR62 localizes to centrosomes in A549, HepG2, and HaCaT cells. In addition, WDR62 was also localized to nucleoli. Bioinformatics analysis predicted two overlapping nuclear localization signals and multiple WD-40 repeats in WDR62. Two other groups have also recently identified WDR62 mutations in MCPH2 families. Our results therefore add further evidence that WDR62 is the MCPH2 gene. The present findings will be helpful in genetic diagnosis of patients linked to the MCPH2 locus.

Psychological problems and quality of life in children with thalassemia

OBJECTIVE

The study is aimed to assess psychological problems and quality of life (QOL) in children with thalassemia.

METHODS

Thirty-nine children (8-16 yr) with transfusion dependent thalassemia attending day care services for blood transfusion were assessed for psychological problems using the Childhood Psychopathology Measurement Schedule and QOL was assessed using the EQ-5D.

RESULTS

Forty-four percent of the children had psychological problems and 74% had a poor QOL. Anxiety-related symptoms (67%), emotional problems, particularly depression (62%) and conduct problems (49%) were the main findings. The children were most likely to report impaired QOL due to severe difficulties in pain/discomfort (64%) dimension, followed by depression and mobility problems of equal severity (33%). The side effects of chelation were an independent predictor of psychological problems and impaired QOL. Also psychological problems were a significant predictor of impaired QOL.

CONCLUSION

The recognition and management of the psychological problems that accompany chronic physical illnesses including thalassemia would optimize treatment outcomes and QOL.

Is bipolar II disorder misdiagnosed as major depressive disorder in children?

OBJECTIVES

To estimate the lifetime prevalence of bipolar II disorder in children and adolescents presenting with DSM-IV major depressive disorder (MDD).

METHODS

Sixty-one consecutive subjects aged < or =18 years attending the outpatient services of the Child and Adolescent Psychiatric (CAP) services of the National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India with a diagnosis of MDD were evaluated using the Missouri Assessment of Genetics Interview for children (MAGIC). Two psychiatrists, one of whom was a child psychiatrist diagnosed hypomania by consensus.

RESULTS

Twelve children had a past episode of hypomania (20%), which was hitherto undiagnosed clinically.

LIMITATIONS

We recruited subjects from a psychiatric hospital, thus limiting the generalizability of the finding. Sample size was relatively small and assessments were cross-sectional.

CONCLUSIONS

: Our study shows that bipolar II disorder is often misdiagnosed as MDD in children. The study also highlights that the chance of diagnosing bipolarity is enhanced by using semi-structured interview in routine clinical practice.

Mutation and polymorphism analysis of TSC1 and TSC2 genes in Indian patients with tuberous sclerosis complex

OBJECTIVE

To find the mutation and polymorphism spectrum of TSC1 and TSC2 genes in patients affected with tuberous sclerosis complex from the Indian population.

MATERIAL AND METHODS

All coding exons and promoter regions of both TSC genes were screened for mutations and polymorphisms in 24 TSC families using polymerase chain reaction-single strand conformation polymorphism and DNA sequencing techniques.

RESULTS

A single previously known mutation, c.2111_2112delAT was identified in the TSC1 gene. A total of 11 mutations were identified in the TSC2 gene. Of these, seven mutations, c.137_138delGA, c.2070delC, c.2087_2088insAA, c.3080T>C (p.L1027P), c.648+1G>A, c.3131+1G>A and c.5034C>G were novel. The remaining four mutations, c.4544_4547delACAA, c.1941_1942insT, c.1831C>T (p.R611W) and c.1832G>A (p.R611Q) had been reported previously in other populations. The novel mutation, c.137_138delGA was predicted to result in the production of a very small tuberin protein of 64 amino acids lacking all seven functional domains. In addition, we also detected three and 10 polymorphisms in the TSC1 and TSC2 genes respectively. DNA sequence analysis of promoter regions of both TSC genes in 24 families did not show any variation.

CONCLUSIONS

This is the first molecular genetic study of TSC in an Indian population. A total of 12 mutations were detected in 24 Indian TSC families in TSC genes. All except one mutation were detected in the TSC2 gene. No variation was found in the promoter regions of either gene. As observed in the western and Japanese populations, the mutations were scattered across the TSC2 gene.

Genetic analysis of primary microcephaly in Indian families: novel ASPM mutations

Patients with primary microcephaly, an autosomal recessive trait, have mild to severe mental retardation without any other neurological deficits. It is a genetically heterogeneous disorder with six known loci: MCPH1 to MCPH6. Only the genes for MCPH1 and MCPH5 have been identified so far. We have ascertained nine consanguineous families with primary microcephaly from India. To establish linkage of these nine families to known MCPH loci, microsatellite markers were selected from the candidate regions of each of the six known MCPH loci and used to genotype the families. The results were suggestive of linkage of three families to the MCPH5 locus and one family to the MCPH2 locus. The remaining five families were not linked to any of the known loci. DNA-sequence analysis identified one known (Arg117X) and two novel (Trp1326X and Gln3060X) mutations in the three MCPH5-linked families in a homozygous state. Three novel normal population variants (i.e., c.7605G > A, c.4449G > A, and c.5961 A > G) were also detected in the ASPM gene.

A follow-up study of juvenile obsessive-compulsive disorder from India

OBJECTIVE

To study the long-term course and outcome of juvenile obsessive-compulsive disorder (OCD).

METHOD

Two to 9-year follow-up of largely self-referred, drug-naïve subjects (n = 58) by employing catch-up longitudinal design.

RESULTS

The mean follow-up period was 5 years. Nearly three-fourth of the sample was adequately treated with medications. Only 21% of the subjects had clinical OCD at follow-up and 48% were in true remission (no OCD and not on treatment). Earlier age-at-onset was associated with better course and outcome.

CONCLUSION

Juvenile OCD has favorable outcome. Our findings are applicable to psychiatric hospital settings in India and perhaps to the general psychiatric settings in the Western countries. Whether the better outcome in this sample is the result of differing clinical characteristics or because of true cross-cultural variation in the course needs further exploration. It is speculated that early onset OCD could be a subtype of juvenile OCD with better outcome.

Comorbidity of mental retardation and affective disorders

Affective disorders in all forms do occur in persons with mental retardation. The presence and degree of mental retardation modify manifestations of these disorders. Diagnosis is difficult because of the absence of classical manifestations and frequent occurrence of inter-episode behaviour disturbances. Response to treatment may not be as favourable as in their normal counterparts.

Comorbidity in juvenile obsessive-compulsive disorder: a report from India

OBJECTIVE

Using minimal exclusion criteria, to assess systematically the psychiatric comorbidity in children and adolescents with obsessive-compulsive disorder (OCD) and compare the findings with those of previous studies.

METHOD

Fifty-four children and adolescents who satisfied DSM-III-R criteria for OCD were assessed using a structured interview schedule, the Children's version of the Yale-Brown Obsessive Compulsive Scale (CY-BOCS), and the questionnaire for tic disorders. All 54 subjects were recruited from the Child and Adolescent Psychiatry (CAP) services of the National Institute of Mental Health and Neuro Sciences (NIMHANS), Bangalore, South India. Diagnoses were determined consensually after a review of all the available data.

RESULTS

Comorbidity was found in 69% of the sample: 22% were diagnosed with disruptive disorders; 20% met criteria for mood disorders; 19% had anxiety disorders; and 17% had tic disorders. Only 1 subject had bipolar disorder, and none had psychosis. The rates for individual diagnoses--in particular, the rates for disruptive disorders, bipolar disorder, and psychosis--were considerably lower than those reported in previous studies.

CONCLUSIONS

Patterns of comorbidity in this study differed from those previously reported. Novel patterns of comorbidity with disruptive disorders, bipolar disorder, and psychosis reported in a few recent studies were not replicated in this study. These differences are probably due to different ascertainment methods. Comorbidity needs to be assessed in large epidemiological samples before definite associations can be made between certain comorbid disorders and juvenile OCD.

Family interview for stress and coping in mental retardation (fisc-mr) : a tool to study stress and coping in families of children with mental retardation

Stress and coping in the families caring for their member with mental retardation has recently received worldwide research attention. There is no comprehensive instrument to study these issues in India. This study reports on development and standardization of a new instrument to fill this lacuna. Family Interview for Stress and Coping in Mental Retardation (FISC - MR), a semi-structured interview schedule, was developed as a part of two years prospective study of efficacy of brief family intervention for 157 children with mental retardation (funded by ICMR). The tool consists of 2 sections - one measuring stress (daily care, emotional, social and financial) and the other measuring mediators of stress or coping strategies (awareness, attitudes, expectations, rearing practices and social support). Results indicate moderate to high reliability (internal consistency, inter-rater reliability and test-retest reliability) and validity (factorial, criterion and construct) of the instrument. It is concluded that FISC -MR is a useful, reliable and valid instrument for both clinical and research purposes.