A novel mutation in the AVPR2 gene in a Palestinian family with nephrogenic diabetes insipidus

Thumbnail Image
Date
2008-11-16
Authors
Dr. Abdulsalam Abu Libdeh
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
<p>Background: Nephrogenic diabetes insipidus (NDI) is a clinical disorder characterized by a urinary concentrating defect resulting from resistance of the collecting duct to the antidiuretic action of vasopressin (AVP). NDI is classified into hereditary and acquired causes. X-linked recessive NDI is caused by mutations in the gene encoding the V2 vasopressin receptor (V2R) and is the most frequent genetic cause of the inherited NDI. Here we describe a novel mutation in the AVPR2 gene in a Palestinian family with NDI.</p> <p>Clinical Data: A male infant, born to a non consanguineous Palestinian family, presented in the neonatal period with failure to thrive, vomiting, irritability &amp; fever. Blood sodium was high up to 170mmol/L, blood osmolality raised over 330mOsm/kg while urine osmolalit remained low between 45-135mOsm/kg, urine output was 7cc/kg/hr &amp; positive family history of a brother diagnosed previously to have NDI suggesting X-linked inheritance of the disease.</p> <p>Molecular Data: Sequencing the AVPR2 gene revealed a novel mutation (C82Y) in affected patients in exon 2 of the gene, predicting Cysteine to Tyrosine substitution at the 82 amino acid residue of the AVPR2 gene, while the mother being carrier for the mutation and healthy brother and father does not have the mutation.</p> <p>Conclusion: We describe a novel mutation in the AVPR2 gene in a Palestinian family with NDI, allowing early diagnosis to prevent severe dehydration and complications in addition to genetic counseling.</p>
<p>Background: Nephrogenic diabetes insipidus (NDI) is a clinical disorder characterized by a urinary concentrating defect resulting from resistance of the collecting duct to the antidiuretic action of vasopressin (AVP). NDI is classified into hereditary and acquired causes. X-linked recessive NDI is caused by mutations in the gene encoding the V2 vasopressin receptor (V2R) and is the most frequent genetic cause of the inherited NDI. Here we describe a novel mutation in the AVPR2 gene in a Palestinian family with NDI.</p> <p>Clinical Data: A male infant, born to a non consanguineous Palestinian family, presented in the neonatal period with failure to thrive, vomiting, irritability &amp; fever. Blood sodium was high up to 170mmol/L, blood osmolality raised over 330mOsm/kg while urine osmolalit remained low between 45-135mOsm/kg, urine output was 7cc/kg/hr &amp; positive family history of a brother diagnosed previously to have NDI suggesting X-linked inheritance of the disease.</p> <p>Molecular Data: Sequencing the AVPR2 gene revealed a novel mutation (C82Y) in affected patients in exon 2 of the gene, predicting Cysteine to Tyrosine substitution at the 82 amino acid residue of the AVPR2 gene, while the mother being carrier for the mutation and healthy brother and father does not have the mutation.</p> <p>Conclusion: We describe a novel mutation in the AVPR2 gene in a Palestinian family with NDI, allowing early diagnosis to prevent severe dehydration and complications in addition to genetic counseling.</p>
Description
Keywords
Citation