Pubmed du 26/02/09

Pubmed du jour

2009-02-26 12:03:50

1. Kumar RA, Marshall CR, Badner JA, Babatz TD, Mukamel Z, Aldinger KA, Sudi J, Brune CW, Goh G, Karamohamed S, Sutcliffe JS, Cook EH, Geschwind DH, Dobyns WB, Scherer SW, Christian SL. {{Association and mutation analyses of 16p11.2 autism candidate genes}}. {PLoS ONE};2009;4(2):e4582.

BACKGROUND: Autism is a complex childhood neurodevelopmental disorder with a strong genetic basis. Microdeletion or duplication of a approximately 500-700-kb genomic rearrangement on 16p11.2 that contains 24 genes represents the second most frequent chromosomal disorder associated with autism. The role of common and rare 16p11.2 sequence variants in autism etiology is unknown. METHODOLOGY/PRINCIPAL FINDINGS: To identify common 16p11.2 variants with a potential role in autism, we performed association studies using existing data generated from three microarray platforms: Affymetrix 5.0 (777 families), Illumina 550 K (943 families), and Affymetrix 500 K (60 families). No common variants were identified that were significantly associated with autism. To look for rare variants, we performed resequencing of coding and promoter regions for eight candidate genes selected based on their known expression patterns and functions. In total, we identified 26 novel variants in autism: 13 exonic (nine non-synonymous, three synonymous, and one untranslated region) and 13 promoter variants. We found a significant association between autism and a coding variant in the seizure-related gene SEZ6L2 (12/1106 autism vs. 3/1161 controls; p = 0.018). Sez6l2 expression in mouse embryos was restricted to the spinal cord and brain. SEZ6L2 expression in human fetal brain was highest in post-mitotic cortical layers, hippocampus, amygdala, and thalamus. Association analysis of SEZ6L2 in an independent sample set failed to replicate our initial findings. CONCLUSIONS/SIGNIFICANCE: We have identified sequence variation in at least one candidate gene in 16p11.2 that may represent a novel genetic risk factor for autism. However, further studies are required to substantiate these preliminary findings.

2. Serour F, Witzling M, Frenkel-Laufer D, Gorenstein A. {{Intestinal obstruction in an autistic adolescent}}. {Pediatr Emerg Care};2008 (Oct);24(10):688-690.

Bezoars and foreign bodies are frequently encountered in children with psychiatric disorders. Eating disorder (called pica) occurs predominantly in some high-risk patients such as psychiatric and mentally disabled children. Small-bowel obstruction is an uncommon complication of ingested foreign body because the foreign body is able to cross the whole small intestine and be excreted in the feces.We present the case history of an autistic adolescent who was operated on because of bowel obstruction due to an unusual foreign body.

3. Tantam D, Girgis S. {{Recognition and treatment of Asperger syndrome in the community}}. {Br Med Bull};2009 (Feb 23)

Sources of data We conducted a systematic review of the current literature for this review, but as there are many gaps in the research literature, we have supplemented this by our own clinical experience. Areas of agreement There is a general agreement that Asperger syndrome (AS) is one of the autistic spectrum disorders, that it is a developmental disorder which is either present at birth or develops shortly after and that there is a strong hereditary component. Areas of controversy The fundamental impairment of AS is in the social arena, but what causes this is disputed. We propose that it is a disorder of non-verbal communication. Another important area of controversy is the extent to which AS may remit. Growing points Many people with AS develop secondary psychiatric disorders in adolescence and adulthood, some of which may be linked genetically, notably bipolar disorder [DeLong R, Nohria C (1994) Psychiatric family history and neurological disease in autistic spectrum disorders. Dev Med Child Neurol, 36, 441-448] or be explicable by some other association, but many patients and carers attribute their anxiety and low mood to bullying. The prevalence, treatment and prevention of co-morbid mental health problems are rapidly developing areas of interest. Some people with AS are known to commit offences, and when they commit they are more likely to be violent offences against strangers. How much of a risk that is presented by people with AS, and how to assess this risk, is another growing area of concern. Areas timely for developing research The social impairments of people with AS include deficits in empathy, self-awareness and executive function. Many of these are quintessentially human characteristics, and the study of people with AS provides opportunities for using neuroimaging to compare people with AS and controls and identify which areas of the brain are concerned with these ‘higher functions’. The study of AS, like that of other fronto-striatal disorders, is also throwing light on the role of networks in the brain and on how networks are formed during embryogenesis.