Yonsei Med J.  2006 Apr;47(2):255-258. 10.3349/ymj.2006.47.2.255.

A Case Report of Familial Benign Hypocalciuric Hypercalcemia: A Mutation in the Calcium-Sensing Receptor Gene

• Woo SI
• Song H
• Song KE
• Kim DJ
• Lee KW
• Kim SJ
• Chung YS

• KMID: 1110751
• DOI: http://doi.org/10.3349/ymj.2006.47.2.255

Abstract

Familial benign hypocalciuric hypercalcemia (FBHH) is an autosomal dominant trait with high penetrance, clinically manifestating a relatively benign, lifelong, persistent hypercalcemia and hypocalciuria without hypercalcemic related complications. The calcium-sensing receptor (CaSR) plays an important role in the regulation of PTH secretion and calcium metabolism. Here we present a family with FBHH of an autosomal dominant inheritance. A heterozygous mutation of E297K (GAG -> AAG, exon 4) of CaSR gene was found in 3 family members. To our knowledge, it is the first confirmed case of FBHH with CaSR gene mutation in Korea.

Keyword

Autosomal dominant; familial; hypocalciuric hypercalcemia; calcium-sensing receptor mutation

MeSH Terms

Sequence Analysis, DNA
Receptors, Calcium-Sensing/*genetics
Pedigree
Parathyroid Hormone/analogs & derivatives/genetics/metabolism
*Mutation
Metabolism, Inborn Errors/*genetics
Male
Korea
Hypercalcemia/*genetics
Humans
Heterozygote
Genes, Dominant
Female
Family Health
Exons
DNA Restriction Enzymes/metabolism
DNA/metabolism
Adult

Figure

• 

  Fig. 1 The direct sequencing analysis of PCR products of the proband. The result revealed a heterozygous mutation of E297K (GAG→AAG, exon 4) of CaSR gene.

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  Fig. 2 Mnl I restriction digest of PCR-amplified DNA from 5 family members. The individual with FBHH exhibits heterozygous loss of an Mnl I site, resulting in the appearance of 74bp fragment derived from the mutant allele, and 47bp + 27bp fragment derived from the normal allele.

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  Fig. 3 Pedigree of the FBHH family. Circles indicate women, squares indicate men, and arrow indicates the proband. Hatched symbols represent individuals with heterozygous E297K mutation.

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