Background/Objective: Prenatal cytogenetic testing is essential for pregnant women who are at high risk of having a child with a chromosomal abnormality. While conventional karyotyping detects large aneuploidies and structural rearrangements (>5–10 Mb), chromosomal microarray analysis (CMA) identifies smaller copy number variants (CNVs), increasing the diagnostic yield by approximately 5%. CMA is now recommended as the first-line test for evaluating fetal structural anomalies that are detected by ultrasound. Method: From March 2023 to September 2024, we analyzed 344 prenatal samples using conventional karyotyping and SNP-based CMA. Karyotyping was performed via flask culture, and CMA was conducted using the Infinium Global Screening Array Cyto (GSA-Cyto) on the Illumina iScan platform. We interpreted the CNVs using NxClinical v6.0 and curated databases including ClinVar, DECIPHER, OMIM, and ClinGen, among others. Our results aligned with the GRCh37/hg19 reference genome. Results: Chromosomal abnormalities were identified in 57/344 cases (16.5%). Of these, 39 cases were numerical chromosomal anomalies, and 18 cases were pathogenic or likely pathogenic CNVs. Notably, 11 CNVs (3.2%) were undetectable by conventional karyotyping, emphasizing the added value of CMA. Conclusions: CMA enhances the prenatal diagnostic accuracy by detecting submicroscopic CNVs that are not visible with conventional methods, supporting the routine use of this analysis in prenatal genetic evaluation.

Objective: A point mutation in the JAK2 gene, resulting in the substitution of valine for phenylalanine (JAK2 V617F), has been associated with myeloproliferative disorders such as polycythemia vera, essential thrombocythemia, idiopathic myelofibrosis, myelodysplastic syndromes, chronic myelomonocytic leukemia, systemic mastocytosis, chronic neutrophilic leukemia, and eosinophilic disorders. Material and Methods: The relation of JAK2 V617F mutation has been studied in myeloproliferative disorder patients by qPCR. The F617 allele was calculated using a standard calibration curve, including less and more than 50% mutational load groups. Results: A significant relation was found among wild type (wt), less and more than 50% groups, Regarding erythrocyte, hematocrit, platelet, and leukocyte levels. A statistically significant relation was found between wt and more than 50% of groups regarding hemoglobin levels. The mutational load increase has been shown to induce erythrocyte, hematocrit, and leukocyte levels, except platelet levels. Conclusion: In patients with myeloproliferative disorders, qPCR screening of JAK2 gene mutation is indicated.