Journal of Genetic Medicine

Korean Society of Medical Genetics and Genomics (대한의학유전학회)
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Genetic Diagnosis of Beckwith Wiedemann Syndrome using Methylation Specific PCR-RFLP Method

Methylation Specific PCR-RFLP 방법을 이용한 Beckwith Wiedemann Syndrome의 진단

  • Kim, Gu-Hwan (Medical Genetics Center, Asan Medical Center Children's Hospital) ;
  • Lee, Jin-Joo (Medical Genetics Center, Asan Medical Center Children's Hospital) ;
  • Choi, Seung-Hoon (Medical Genetics Center, Asan Medical Center Children's Hospital) ;
  • Lee, Joo-Yeon (Medical Genetics Center, Asan Medical Center Children's Hospital) ;
  • Lee, Beom-Hee (Medical Genetics Center, Asan Medical Center Children's Hospital) ;
  • Yoo, Han-Wook (Medical Genetics Center, Asan Medical Center Children's Hospital)
  • 김구환 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉) ;
  • 이진주 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉) ;
  • 최성훈 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉) ;
  • 이주연 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉) ;
  • 이범희 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉) ;
  • 유한욱 (울산대학교 의과대학, 서울아산병원 소아청소년병원, 의학유전학클리닉)
  • Received : 2010.11.28
  • Accepted : 2010.12.15
  • Published : 2010.12.01
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Abstract

Purpose: Beckwith-Wiedemann syndrome (BWS) is an overgrowth malformation syndrome caused by a methylation abnormality at chromosome 11p15, consisting of two imprinting centers, BWSIC1 (IGF2, H19) and BWSIC2 (LIT1, KvDMR). This study evaluated the applicability of a methylation-specific (MS) PCR RFLP method for the genetic diagnosis of BWS. Materials and Methods: A total of 12 patients were recruited based on clinical findings. Karyotyping was performed using peripheral blood leukocytes, and genomic DNA was treated with bisulfate and amplified using methylation-specific primers. RFLP was conducted with restriction enzymes in differentially methylated regions of LIT1, H19, and IGF2. Results: The 12 BWS patients had normal karyotypes. Abnormal methylation patterns in the BWSIC2 (LIT1) region were identified in seven patients (58.3%) using the MS-PCR RFLP method. Conclusions: The MS-PCR RFLP method is a simple, economical genetic test. It detected genetic abnormalities in 50-60% of BWS patients, suggesting that it can be used as a screening test. A more precise method is required, however, to enhance the detection rate of genetic abnormalities, especially in BWSIC1 region.

목 적: Beckwith-Wiedemann 증후군(BWS)은 11p15 부위의 메칠화 양상의 이상으로 인한 overgrowth malformation symdrome이다. 11p15 부위에는 두 가지 imprinting center, 즉BWSIC1 (IGF2, H19)와 BWSIC2 (LIT1,KvDMR)가 존재한다. 본 연구에서는 methylation-specific (MS) PCR RFLP 방법을 이용한 BWS의 유전적 진단을 보고하고자 한다. 대상 및 방법: 임상 소견을 바탕으로 12명의 BWS 환자가 포함되었다. 환자의 말초혈액으로부터 염색체 핵형을 조사하였다. 분리한 DNA에 bisulfite를 처리한 후, LIT1, H19, IGF2 DMR부위는 각각의 MS primer를 이용하여 증폭하였다. 적절한 제한효소를 이용하여 절단 여부를 PAGE로 확인함으로써 각각의 DMR 부위에 대한 메칠화 이상 여부를 확인하였다. 결 과: 12명의 환자는 모두 정상 핵형을 보였다. MS-PCR RFLP 상 총 7명(53.8%)의 환자가 이상 소견을 보였으며, 모두 BWSIC2 (LIT1)에 비정상적 메칠화를 보였고 모두 부계 유래의 비메칠화된 allele만이 발견되었다. 결 론: 본 연구를통해MS-PCR RFLP 검사로BWS 환자의 약 50-60% 정도에서 유전적 진단이 가능함을 알 수 있었으며, 이는 BWSIC2 부위의 메칠화 이상을 발견하는데 손쉽게 이용될 수 있을 것으로 판단된다. 그러나, BWSIC1 부위의 메칠화 이상은 발견이 어려우며, 이 부위의 이상을 발견하기 위해서는 메칠화를 정량적으로 분석할 수 있는 방법이 필요하다.

Keywords

References

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