Abstract
Familial neurohypophyseal diabetes insipidus (FNDI) is an autosomal dominant
hereditary disorder characterized by severe polydipsia and polyuria that
usually presents in early childhood. In this study, we describe a new
arginine vasopressin (AVP) gene mutation in an ethnic German family with
FNDI and provide an overview of disease-associated AVP-gene mutations that
are already described in literature. Three members of a German family with
neurohypophyseal diabetes insipidus were studied. Isolated DNA from
peripheral blood samples was used for mutation analysis by sequencing the
whole coding region of AVP-NPII gene. Furthermore, we searched the
electronic databases MEDLINE (Pubmed) as well as HGMD, LOVD-ClinVar, db-SNP
and genomAD in order to compare our cases to that of other patients with
FNDI. Genetic analysis of the patients revealed a novel heterozygote
missense mutation in exon 2 of the AVP gene (c.274T>G), which has
not yet been described in literature. We identified reports of more than 90
disease-associated mutations in the AVP gene in literature. The novel
mutation of the AVP gene seems to cause FNDI in the presented German family.
Similar to our newly detected mutation, most mutations causing FNDI are
found in exon 2 of the AVP gene coding for neurophysin II. Clinically, it is
important to think of FNDI in young children presenting with polydipsia and
polyuria.
Key words
desmopressin - AVP-NPII gene - neurohypophyseal diabetes insipidus - AVP