Journal of Genetic Medicine

  • 제18권1호
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  • Pages.64-69
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  • 2021
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  • 1226-1769(pISSN)
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  • 2383-8442(eISSN)
대한의학유전학회 (Korean Society of Medical Genetics and Genomics)
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A case of TBC1D32-related ciliopathy with novel compound heterozygous variants

  • Ahn, Ji Ye (Department of Pediatrics, Pediatric Neuroscience Center, Seoul National University Children's Hospital) ;
  • Kim, Soo Yeon (Department of Pediatrics, Pediatric Neuroscience Center, Seoul National University Children's Hospital) ;
  • Lim, Byung Chan (Department of Pediatrics, Pediatric Neuroscience Center, Seoul National University Children's Hospital) ;
  • Kim, Ki Joong (Department of Pediatrics, Pediatric Neuroscience Center, Seoul National University Children's Hospital) ;
  • Chae, Jong Hee (Department of Pediatrics, Pediatric Neuroscience Center, Seoul National University Children's Hospital)
  • 투고 : 2020.12.16
  • 심사 : 2021.02.03
  • 발행 : 2021.06.30
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초록

Primary cilium has a signal transduction function that is essential for brain development, and also determines cell polarity and acts as a mediator for important signaling systems, especially the Sonic Hedgehog (SHH) pathway. TBC1D32 is a ciliary protein, implicated in SHH signaling. Biallelic mutations in the TBC1D32 gene causes a kind of ciliopathy, heterogeneous developmental or degenerative disorders that affect multiple organs, including the brain. Here we report a boy who carried compound heterozygous variants in TBC1D32. The patient showed hypotonia, respiratory difficulty, and multiple anomalies at his birth. He was diagnosed with congenital hypopituitarism and treated with T4, hydrocortisone, and growth hormone. Despite the hormonal replacement, the patient needed long-term respiratory support with tracheostomy and nutritional support with a feeding tube. His developmental milestones were severely retarded. Hydrocephalus and strabismus developed and both required surgery, during the outpatient follow-up. Whole-exome sequencing indicated compound heterozygous variants, c.2200C>T (p.Arg734*) and c.156-1G>T, in TBC1D32 gene. This is the first Korean case of TBC1D32-related ciliopathy and we reported detailed and sequential clinical features. This case demonstrated the utility of whole-exome sequencing and provided valuable clinical data on ultra-rare disease.

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과제정보

This study was supported by the Research Program funded by the Korea Centers for Disease Control and Prevention (Grant No. 2018-ER6901-02).

참고문헌

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