Apparent mineralocorticoid excess caused by novel compound heterozygous mutations in HSD11B2 and characterized by early-onset hypertension and hypokalemia

Abstract

Purpose Apparent mineralocorticoid excess (AME) is an ultrarare autosomal recessive disorder resulting from deficiency of 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) caused by mutations in HSD11B2. The purpose of this study was to identify novel compound heterozygous HSD11B2 mutations in a Chinese pedigree with AME and conduct a systematic review evaluating the AME clinical features associated with HSD11B2 mutations. Methods Next-generation sequencing was performed in the proband, and Sanger sequencing was used to identify candidate variants in family members, 100 hypertensives, and 100 healthy controls. A predicted structure of 11βHSD2 was constructed by in silico modeling. A systematic review was used to identify cases of HSD11B2-related AME. Data for genotyping and clinical characterizations and complications were extracted. Results Next-generation sequencing showed novel compound heterozygous mutations (c.343_348del and c.1099_1101del) in the proband with early-onset hypertension and hypokalemia. Sanger sequencing verified the monoallelic form of the same mutations in five other relatives but not in 100 hypertensives or 100 healthy subjects. In silico structural modeling showed that compound mutations may simultaneously perturb the substrate and coenzyme binding pocket. A systematic review of 101 AME patients with 54 HSD11B2 mutations revealed early-onset hypertension, hypokalemia and homozygous mutations as common features. The homozygous HSD11B2 mutations correlated with low birth weight (r = 0.285, P = 0.02). Conclusions We report novel compound heterozygous HSD11B2 mutations in a Chinese teenager with early-onset hypertension, and enriched genotypic and phenotypic spectrums in AME. Genetic testing helps early diagnosis and treatment for AME patients, which may avoid target organ damage.

Identification of novel prognostic targets in acute kidney injury using bioinformatics and next generation sequencing data analysis

“…BMI1 [245], CCL5 [246], GREM1 [247], ANGPTL3 [248], ARG2 [249], MSRA (methionine sulfoxidereductase A) [250], SNCA (synuclein alpha) [251], NOX4 [252], PFKFB2 [253], PDZK1 [254], SUCNR1 [255], LYVE1 [256], AZGP1 [257], ERBB4 [258] and PLAT (plasminogen activator, tissue type) [259] might serve as molecular markers for kidney fibrosis. BMI1 [260], IGF2 [261], IRF7 [262], CCL5 [263], ACTN3 [264], E2F1 [265], PF4 [266], TEAD4 [267], TBX4 [268], GREM1 [269], CYP11B2 [270], WNT3A [124], COMP (cartilage oligomeric matrix protein) [271], FLI1 [272], RAP1B [273], ANGPTL3 [274], CYP3A5 [275], HSD11B2 [276], HMGCS2 [277], AGXT2 [278], SLC22A12 [279], FGF1 [280], CRY1 [281], PPARGC1A [282], SLC19A3 [283], CYP2C8 [284], ACOX2 [285], SLC2A9 [286], MSRA (methionine sulfoxidereductase A) [287], VNN1 [288], EPHX2 [289], CROT (carnitine O-octanoyltransferase) [290], SCNN1B [291], NR4A3 [292], HSD17B7 [293], SLC22A2 [294], AQP2 [295], SLC2A2 [296], EGF (epidermal growth factor) [297], ANGPT1 [298], SLC26A4 [299], KL (klotho) [300], SCNN1G [301], PDZK1 [302], PTPRD (protein tyrosine phosphatase receptor type D) [303], ACE2 [304], FOLH1 [305], SUCNR1 [306], GLCE (glucuronic acid epimerase) [307], AQP3 [308], DPP4 [309], REN (renin) [310], TRPM6 [311], ABCB1 [312], MTTP (microsomal triglyceride transfer protein) [313], CALCRL (calcitonin receptor like receptor) [314], ENPEP (glutamylaminopept...…”

Low renin forms of monogenic hypertension: review of the evidence

“…• Apparent Mineralocorticoid Excess (AME) Apparent Mineralocorticoid Excess (AME), more specifically known as Classic AME [51], is an infrequent monogenic hypertensive disorder with about 100 reported cases worldwide [52]. First reported in the 1970s [53], it was not until 1995 that the first mutation was found [52].…”

Summary of Known Genetic and Epigenetic Modification Contributed to Hypertension

“…Primarily expressed in sodium-transporting epithelia, the HSD11B2 enzyme facilitates the metabolic conversion of cortisol to its inactive form, cortisone, at aldosterone binding sites thus protecting mineralocorticoid receptors (MRs) from cortisol excess [ 25 ]. In the compromised HSD11B2 activity as a result of mutation, the MRs were overstimulated by cortisol causing intense water and sodium retention, hypokalaemia, and hypertension [ 26 ]. To date, about 40 causative mutations in the HSD11B2 gene have been recognized [ 27 ].…”

“…Utilizing the next-generation sequencing (NGS) and Sanger sequencing, Fan et al [ 26 ] found that a paternally inherited c.343_348del and maternally inherited c.1099_1101del variant were detected in exon 2 and 5 of a teenager with AME. Both mutations are characterized to result in Glu115 deletion, Leu116 deletion, a truncated 11 β HSD2 protein production, and Phe367 deletion.…”