Journal of The Korean Society of Inherited Metabolic disease (대한유전성대사질환학회지)

The Korea Society of Inherited Metabolic Disease (대한유전성대사질환학회)
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Hypocalcemic Tetany in a 10-year Old Boy: A Case of Pseudohypoparathyroidism Type 1b due to Paternal Uniparental Disomy

간헐적 강직을 주소로 내원한 저칼슘혈증 10세 남아: 부계 단친성 이염색체로 인한 가성부갑상샘기능저하증 1b형 증례

  • Yoo, Byung Min (Department of Pediatrics, Hallym University College of Medicine) ;
  • Kim, Mijin (Department of Pediatrics, Hallym University College of Medicine) ;
  • Ko, Jung Min (Department of Pediatrics, Seoul National University College of Medicine) ;
  • Kang, Min Jae (Department of Pediatrics, Hallym University College of Medicine)
  • 유병민 (한림대학교 의과대학 소아청소년과) ;
  • 김미진 (한림대학교 의과대학 소아청소년과) ;
  • 고정민 (서울대학교 의과대학 소아청소년과) ;
  • 강민재 (한림대학교 의과대학 소아청소년과)
  • Published : 2020.12.31
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Abstract

Pseudohypoparathyroidism (PHP) is a disorder characterized by hypocalcemia and hyperphosphatemia due to end organ resistance to parathyroid hormone. PHP is caused by the deficiency of the α-subunit of the stimulatory G protein encoded by the GNAS gene, and this defect arises from genetic or imprinting disturbances. Sporadic PHP 1b shows two or more methylation defects of upstream of GNAS gene and some of them lead to loss of maternal GNAS imprints, therefore, only paternally derived GNAS gene is expressed. Here, we report a 10 year 9 month old boy presented with intermittent tetany who was finally diagnosed with PHP 1b caused by paternal uniparental disomy of chromosome 20q.

가성부갑상샘기능저하증(pseudohypoparathyroidism, PHP)은 부갑상샘호르몬에 대해 표적 기관이 저항성을 가지며, 저칼슘혈증과 고인산혈증을 특징으로 하는 질병이다. PHP의 원인은 자극형 G 단백의 신호전달이 문제인데, α-아형을 인코딩하는 GNAS 유전자와 GNAS 유전자 상부의 각인 이상으로 발생한다. 가족력 없이 발생하는 산발성 PHP 1b형은 GNAS 유전자 상류 다발 지역의 메칠화 이상으로, 그 중 일부는 모계 유전형이 소실되고, 부계 유전형만이 표현된다. 본 논문에서는 간헐적 강직을 주소로 내원한 10.8세 남아에서 발생한 20번 염색체 장완의 부계 단친성 이염색체에 의한 산발성 PHP 1b형의 증례를 고찰해보고자 한다.

Keywords

References

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