In nerve conduction studies, findings consistent with distal prominent motor axonal neuropathy were observed (Table 1). The patient's cognitive functions and brain MR imaging are within normal limits. TABLE 1. NERVE CONDUCTION STUDIES AT THE FIRST ADMISSION OF THE PATIENT. GENETIC EVALUATION DNA extraction was performed according to instructions (Maxwell RSC Blood DNA kit, Promega, USA). The concentration of DNA samples was determined using Qubit 3.0 (Thermo Fisher Scientific). The libraries for sequencing were constructed following the instructions of Twist Human Core Exome Kit protocol (Twist Bioscience, USA). Next-gene sequencing was performed on a Novaseq system (Illumina, USA). Sequence data analysis using Sophia DDM (Switzerland). The analysis revealed a homozygous variation (c.755G>T p.(Gly252Val)) in the SORD gene. On the other hand, silico prediction data bases, such as MetaRNN, BayesDel, PROVEAN, CADD, SIFT indicated that the variation was classified as 'pathogenic.' In addition, this variant has not been observed as homozygous in the healthy population according to Genome Aggregation Database (gnomAD). According to the American College of Medical Genetics (ACMG) 2015 criteria (Richards S, Aziz N, Bale S, et al. Standards and Guidelines for the Interpretation of Sequence Variants: a Joint Consensus Recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genet Med. 2015 May; 17 (5): 405-24.), the variant was clas-sified as class 3 clinical significance. Our opinion that given the similarity between the patient's clinical presentation and the expected findings of the sorbitol dehydrogenase deficiency phenotype caused by homozygous pathogenic variant features, the patient in the similar variant has the expected findings of the sorbitol dehydrogenase deficiency with peripheral neuropathy. * BA?A D?N * ?ZET * GIRI? * OLGU SUNUSU * TART??MA * KAYNAKLAR