Akademik Veri Yönetim Sistemi
International Hereditary Cancers Congress, Antalya, Türkiye, 6 - 08 Şubat 2025, ss.98-102, (Özet Bildiri)
Neurofibromatosis type 1 (NF1, OMIM #162200) is an autosomal dominant disorder characterized by café-au-lait
macules, Lisch nodules, optic pathway gliomas, intertriginous freckling, osseous lesions, and cutaneous
neurofibromas with an increased susceptibility to tumor formation. The NF1 gene functions as a tumor suppressor,
playing a critical role in regulating cell growth and development. This study presents the molecular and clinical
findings of patients diagnosed with Neurofibromatosis type 1 at Eskişehir Osmangazi University Department of
Medical Genetics between 2014 and 2024. The median age at diagnosis ranged from 2 to 51 years, with a mean of
25.2 years. A heterozygous pathogenic variant in the NF1 gene or a microdeletion involving the NF1 gene was
identified in 37 patients. The most common clinical and molecular findings are summarized in Table 1. Among the
identified variants, two (5%) were microdeletions, five (13%) were missense variants and 29 (78%) were nonsense
variants. Three variants (11%) were novel, while 34 variants (89%) had been previously reported in the literature.
Variants were classified according to ACMG criteria: 28 (75%) were pathogenic, seven (18%) were likely
pathogenic, and two (5%) were variants of uncertain significance (VUS). Family members with similar clinical
findings were identified in 16 patients. Sanger sequencing of known variants was recommended for family members
and screening suggestions were provided in line with current clinical guidelines. Through this study, we aim to
contribute to the literature by reporting novel NF1 variants and exploring genotype-phenotype correlations in our
Turkish patient cohort.