title: Towards a new point of view on the phenotype of patients with a 17q12 microdeletion syndrome.
abstract: OBJECTIVE
  17q12 microdeletion syndrome involves 15 genes, including HNF1B, and is considered to confer a high risk of neuropsychiatric disorders. Patients with HNF1B gene deletion diagnosed secondary to renal disorders are only very rarely reported to have neuropsychiatric disorders. Interestingly, however, when tested, patients with HNF1B gene deletion are found to have 17q12 deletion. This brings into question the extent to which 17q12 deletion is genuinely associated with severe neuropsychological disorders and in which patients. In this study, we sought to confirm 17q12 microdeletion in kidney patients initially diagnosed with HNF1B gene deletion and evaluate neuropsychological disorders in these patients compared with those with HNF1B point mutation.
  
  
  METHODS
  Thirty-nine children with HNF1B disorders (26 with deletions) diagnosed secondary to renal abnormalities were included in this prospective study and tested for 17q12 microdeletion and neuropsychological disorders.
  
  
  RESULTS
  The same 17q12 microdeletion found in patients with neuropsychological disorders was identified in all of our patients with HNF1B deletion. Neurological examinations found no severe impairments except for one patient with autism. No significant differences were found between patients with deletions and those with point mutations as concerns learning abilities and schooling. Nevertheless, patients with deletions tended to have lower developmental quotients and more difficulties at school.
  
  
  CONCLUSIONS
  Complete deletion of the HNF1B gene and 17q12 microdeletion syndrome are actually the same genetic disorder. The neuropsychological phenotype of patients appears less severe when 17q12 deletion is diagnosed secondary to kidney rather than neuropsychological abnormalities. These data may influence antenatal counselling.
authors.affiliation: Department of Paediatrics, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Fanny
authors.initials: F
authors.lastname: Laffargue
authors.affiliation: Department of Cytogenetic, CHREC, Limoges University Hospital, Limoges, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Bourthoumieu
authors.affiliation: Department of Paediatric Nephrology, Bordeaux University Hospital, Bordeaux, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Llanas
authors.affiliation: Department of Paediatric Nephrology, Hospital R. Debré, APHP, Paris, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Baudouin
authors.affiliation: Department of Paediatric Nephrology, Lille University Hospital, Lille, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Lahoche
authors.affiliation: Department of Paediatric Nephrology, Montpellier University Hospital, Montpellier, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Morin
authors.affiliation: Department of Paediatric Nephrology, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Bessenay
authors.affiliation: Department of Paediatric Nephrology, Brest University Hospital, Brest, France.
authors.forename: Loïc
authors.initials: L
authors.lastname: De Parscau
authors.affiliation: Department of Paediatric Nephrology, Tours University Hospital, Tours, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Cloarec
authors.affiliation: Department of Medical Genetics, CHU Bordeaux, Rare Diseases Laboratory: Genetics and Metabolism (MRGM), University of Bordeaux, Bordeaux, France.
authors.forename: Marie-Ange
authors.initials: MA
authors.lastname: Delrue
authors.affiliation: Department of Paediatric Nephrology, Bordeaux University Hospital, Bordeaux, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Taupiac
authors.affiliation: Department of Paediatrics, CHREC, Limoges University Hospital, Limoges, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Dizier
authors.affiliation: Department of Paediatrics, CHREC, Limoges University Hospital, Limoges, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Laroche
authors.affiliation: Department of Paediatrics, CHREC, Limoges University Hospital, Limoges, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Bahans
authors.affiliation: Department of Cytogenetic, CHREC, Limoges University Hospital, Limoges, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Yardin
authors.affiliation: Department of Medical Genetics, CHU Bordeaux, Rare Diseases Laboratory: Genetics and Metabolism (MRGM), University of Bordeaux, Bordeaux, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Lacombe
authors.affiliation: Department of Paediatrics, CHREC, Limoges University Hospital, Limoges, France CNRS UMR 7276, Limoges University, Limoges, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Guigonis
mesh_terms: D000293:Adolescent; D002493:Central Nervous System Diseases / Q000150:complications / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D003743:Dental Enamel / Q000002:abnormalities*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000235:genetics*; D005260:Female; D005602:France; D051539:Hepatocyte Nuclear Factor 1-beta / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D052177:Kidney Diseases, Cystic / Q000150:complications / Q000235:genetics*; D008297:Male; D001523:Mental Disorders / Q000235:genetics*; D010641:Phenotype; D011446:Prospective Studies
chemical_list: C496495:HNF1B protein, human; D051539:Hepatocyte Nuclear Factor 1-beta
keywords: Genetics; Nephrology; Neurodevelopment