<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Small supernumerary marker chromosome (sSMC) is a rare chromosomal abnormality and is detected in about 0.3% in cases with multiple congenital anomalies (MCA) and/or developmental delay. Different techniques for investigation of cases with MCA and/or developmental delay are available ranging from karyotyping to molecular cytogenetic technique and ultimately multiplex ligation dependent probe amplification (MLPA). Here we present a patient with multiple congenital anomalies for which classical cytogenetic technique was used as a first step in diagnosis and the results being confirmed by MLPA. The karyotype disclosed a sSMC considered to be a fragment of chromosome 22. The MLPA analysis using SALSA MLPA probemix P064-C2 Microdeletion Syndromes-1B confirmed the karyotype results, and according to the manufacturer’s recommendation we performed another confirmation analysis with MLPA probemix P311-B1 Congenital Heart Disease and MLPA probemix P250-B2 DiGeorge. We also suspected an Emanuel syndrome and performed another MLPA analysis with SALSA MLPA probemix P036-E3 Subtelomeres Mix 1 and probemix P070-B3 Subtelomeres Mix 2B for investigation of subtelomeric region that revealed a duplication of 11q25 region and the confirmation was performed using SALSA MLPA probemix P286-B2 Human Telomere-11.</p><p>In conclusion, we consider that MLPA is a valuable method for identification of sSMC in children with developmental delay and congenital anomalies. Genetic diagnosis using different molecular techniques, such as MLPA, for increasing accuracy in identification of chromosomal structural aberrations has an important role in clinical diagnosis and in genetic counselling and our case explain the importance of using a specific laboratory technique for each stage of diagnosis.</p></abstract>

Small supernumerary marker chromosome (sSMC) is a rare chromosomal abnormality and is detected in about 0.3% in cases with multiple congenital anomalies (MCA) and/or developmental delay. Different techniques for investigation of cases with MCA and/or developmental delay are available ranging from karyotyping to molecular cytogenetic technique and ultimately multiplex ligation dependent probe amplification (MLPA). Here we present a patient with multiple congenital anomalies for which classical cytogenetic technique was used as a first step in diagnosis and the results being confirmed by MLPA. The karyotype disclosed a sSMC considered to be a fragment of chromosome 22. The MLPA analysis using SALSA MLPA probemix P064-C2 Microdeletion Syndromes-1B confirmed the karyotype results, and according to the manufacturer’s recommendation we performed another confirmation analysis with MLPA probemix P311-B1 Congenital Heart Disease and MLPA probemix P250-B2 DiGeorge. We also suspected an Emanuel syndrome and performed another MLPA analysis with SALSA MLPA probemix P036-E3 Subtelomeres Mix 1 and probemix P070-B3 Subtelomeres Mix 2B for investigation of subtelomeric region that revealed a duplication of 11q25 region and the confirmation was performed using SALSA MLPA probemix P286-B2 Human Telomere-11.In conclusion, we consider that MLPA is a valuable method for identification of sSMC in children with developmental delay and congenital anomalies. Genetic diagnosis using different molecular techniques, such as MLPA, for increasing accuracy in identification of chromosomal structural aberrations has an important role in clinical diagnosis and in genetic counselling and our case explain the importance of using a specific laboratory technique for each stage of diagnosis.

Multiplex ligation dependent probe amplification - A useful, fast and cost-effective method for identification of small supernumerary marker chromosome in children with developmental delay and congenital heart defect

University of Medicine, Pharmacy, Sciences and Technology of Târgu Mureş

Center for Advanced Medical and Pharmaceutical Research

Department of Pediatrics III, Cardiology Clinic II – Children

Revista Romana de Medicina de Laborator

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Small supernumerary marker chromosome (sSMC) is a rare chromosomal abnormality and is detected in about 0.3% in cases with multiple congenital anomalies (MCA)...

Multiplex ligation dependent probe amplification - A useful, fast and cost-effective method for identification of small supernumerary marker chromosome in children with developmental delay and congenital heart defect

Published Online: Oct 29, 2018

Page range: 461 - 470

Received: Aug 06, 2018

Accepted: Sep 18, 2018

DOI: https://doi.org/10.2478/rrlm-2018-0032

Keywords
supernumerary marker chromosomes, multiplex ligation dependent probe amplification, congenital anomalies

© 2018 George Andrei Crauciuc et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Multiplex ligation dependent probe amplification - A useful, fast and cost-effective method for identification of small supernumerary marker chromosome in children with developmental delay and congenital heart defect

Published Online: Oct 29, 2018

Page range: 461 - 470

Received: Aug 06, 2018

Accepted: Sep 18, 2018

DOI: https://doi.org/10.2478/rrlm-2018-0032

Keywordssupernumerary marker chromosomes, multiplex ligation dependent probe amplification, congenital anomalies

© 2018 George Andrei Crauciuc et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
supernumerary marker chromosomes, multiplex ligation dependent probe amplification, congenital anomalies