PUBLICATION
CRB2 mutations produce a phenotype resembling congenital nephrosis, Finnish type, with cerebral ventriculomegaly and raised alpha-fetoprotein
- Authors
- Slavotinek, A., Kaylor, J., Pierce, H., Cahr, M., DeWard, S.J., Schneidman-Duhovny, D., Alsadah, A., Salem, F., Schmajuk, G., Mehta, L.
- ID
- ZDB-PUB-170214-233
- Date
- 2015
- Source
- American journal of human genetics 96: 162-9 (Journal)
- Registered Authors
- Slavotinek, Anne
- Keywords
- none
- MeSH Terms
-
- Amniotic Fluid/metabolism
- Carrier Proteins/genetics*
- Carrier Proteins/metabolism
- Child
- Female
- Fetus
- Genetic Variation
- Humans
- Hydrocephalus/genetics*
- Male
- Membrane Proteins/genetics*
- Membrane Proteins/metabolism
- Nephrotic Syndrome/genetics*
- Phenotype
- Pregnancy
- Protein Structure, Secondary
- alpha-Fetoproteins/metabolism*
- PubMed
- 25557780 Full text @ Am. J. Hum. Genet.
Citation
Slavotinek, A., Kaylor, J., Pierce, H., Cahr, M., DeWard, S.J., Schneidman-Duhovny, D., Alsadah, A., Salem, F., Schmajuk, G., Mehta, L. (2015) CRB2 mutations produce a phenotype resembling congenital nephrosis, Finnish type, with cerebral ventriculomegaly and raised alpha-fetoprotein. American journal of human genetics. 96:162-9.
Abstract
We report five fetuses and a child from three families who shared a phenotype comprising cerebral ventriculomegaly and echogenic kidneys with histopathological findings of congenital nephrosis. The presenting features were greatly elevated maternal serum alpha-fetoprotein (MSAFP) or amniotic fluid alpha-fetoprotein (AFAFP) levels or abnormalities visualized on ultrasound scan during the second trimester of pregnancy. Exome sequencing revealed deleterious sequence variants in Crumbs, Drosophila, Homolog of, 2 (CRB2) consistent with autosomal-recessive inheritance. Two fetuses with cerebral ventriculomegaly and renal microcysts were compound heterozygotes for p.Asn800Lys and p.Trp759Ter, one fetus with renal microcysts was a compound heterozygote for p.Glu643Ala and p.Asn800Lys, and one child with cerebral ventriculomegaly, periventricular heterotopias, echogenic kidneys, and renal failure was homozygous for p.Arg633Trp in CRB2. Examination of the kidneys in one fetus showed tubular cysts at the corticomedullary junction and diffuse effacement of the epithelial foot processes and microvillous transformation of the renal podocytes, findings that were similar to those reported in congenital nephrotic syndrome, Finnish type, that is caused by mutations in nephrin (NPHS1). Loss of function for crb2b and nphs1 in Danio rerio were previously shown to result in loss of the slit diaphragms of the podocytes, leading to the hypothesis that nephrosis develops from an inability to develop a functional glomerular barrier. We conclude that the phenotype associated with CRB2 mutations is pleiotropic and that the condition is an important consideration in the evaluation of high MSAFP/AFAFP where a renal cause is suspected.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping