Evaluation of 6 Patients with Chromosome 18 Structural Anomalies and Novel Findings

INTRODUCTION: Structural chromosome 18 anomalies are characterized by multiple congenital anomalies and intellectual disability. In this study, 6 cases with structural anomalies of chromosome 18 diagnosed by using conventional and molecular cytogenetic analyses are presented.
METHODS: Six cases who were carrying structural chromosome 18 abnormalities were enrolled in the study. Developmental milestones, growth parameters and dysmorphologic features were evaluated by experienced clinical geneticists. Laboratory analysis including genetic tests, imaging studies, eye and hearing examinations were obtained from medical records, retrospectively.
RESULTS: All cases had karyotype analysis, 2 cases had fluorescence in situ hybridization analysis and one case had microarray analysis which were performed by using peripheral blood. A total of 6 cases in which del(18p) in one case, del(18q) in 4 cases and i(18q) in one case were evaluated.
DISCUSSION AND CONCLUSION: Although a wide range of phenotypic findings could be seen in patients who carry structural chromosome 18 anomalies depending on affected chromosomal region and size, some additional novel features are presented in our series which will contribute to the literature.