pam med j Pamukkale Medical Journal 1308-0865 Pamukkale University 10.31362/patd.1850985 Medical Genetics (Excl. Cancer Genetics) Tıbbi Genetik (Kanser Genetiği hariç) Curating genes at 20p13 to identify candidate genes for terminal microdeletions Terminal 20p13 delesyonlarına aday genleri tanımlamak https://orcid.org/0000-0001-6461-0957 Okur Volkan New York Genome Center https://orcid.org/0009-0009-1158-7541 Lee Alexandra The Warren Alpert Medical School of Brown University https://orcid.org/0000-0001-8016-5224 Kendir Demirkol Yasemin New York Genome Center 04 13 2026 19 2 403 411 12 29 2025 02 10 2026 Copyright © 2008, Pamukkale Medical Journal 2008 Pamukkale Medical Journal

Purpose: Microdeletions are well-known drivers of genetic disorders. Generally, a few genes are identified as driver genes for the observed phenotypes in microdeletion carriers. In this study, we interrogated the 20p13 terminal region to identify candidate gene(s) primarily for the neurodevelopmental disorders in individuals with 20p13 terminal microdeletions.Materials and methods: Publicly available information on gene functions, gene expressions, gene-disease relationships, and populational genomic data are used to identify genes within the terminal 2.5 Mb region of 20p13 that are tolerant or intolerant to deletions and loss-of-function variants.Results: CSNK2A1 has the highest intolerance metrics to both deletion and loss-of-function variation among the 40 protein-coding genes within the terminal 2.5 Mb at 20p13, followed by SNPH when the rest of the genes are also evaluated by their gene functions and expression patterns.Conclusion: We propose that CSNK2A1 is the main driver gene for the neurodevelopmental disorder/intellectual disability phenotypes in individuals with microdeletions encompassing genes within the terminal 2.5 Mb at 20p13 region.

Amaç: Mikrodelesyonların genetik sendromlara yol açtığı bilinmektedir. Genellikle bir veya iki gen, gözlenen fenotiplerin ana nedeni olarak öne çıkarılır. Bu çalışmada, 20p13 mikrodelesyonu olan bireylerdeki fenotiplere yol açan major genleri tanımlamak amacıyla 20p13 terminal bölgesini araştırdık.Gereç ve yöntem: 20p13’ün terminal 2.5 Mb bölgesi içinde delesyonlara toleranslı ve toleranssız genleri belirlemek amacıyla gen fonksiyonları, gen ekspresyonu ve gen–hastalık ilişkisi bilgileri ile delesyonlar ve fonksiyon kaybı varyantlarına ilişkin popülasyon verileri kullanılmıştır.Bulgular: CSNK2A1 20p13’ün terminal 2.5 Mb bölgesi içinde yer alan 40 protein-kodlayan gen arasında en yüksek intolerans skorlarına sahip gendir ve onu SNPH takip etmektedir.Sonuç: 20p13’ün terminal 2.5 Mb bölgesi içindeki genleri kapsayan mikrodelesyonlara sahip bireylerde görülen nörogelişimsel ve davranışsal bozukluk fenotiplerinin ana sürücü geninin CSNK2A1 olduğunu öne sürüyoruz.

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