Introduction: Short tandem repeats (STRs) have been used for various identity typing methods worldwide. They have high discrimination power in human identification in forensics, paternity testing, missed personal identification, genetic diseases, and gene regulatory functions. They have also been used to detect and monitor the stability of diseases, including various types of cancer. This study aimed to investigate the impact of leukemia on the detection and stability of STR markers.Methods: DNA was isolated from 30 participants (15 with chronic myeloid leukemia( CML) and 15 healthy controls) and used to amplify STR markers using specific primers.Results: We found that the blood of those with leukemia had more 9.3 and 9 alleles at the tyrosine hydroxylase 1 (TH01) marker than the blood of the healthy control samples. The results of this study will help researchers understand leukemia's effect on the detection and stability of STR markers in leukemic patients compared to healthy individuals. Conclusion:Our results demonstrate that STR markers could become useful in genetic studies of leukemia cases.

Background: Transcobalamin (TC) is a carrier protein and it delivers vitamin B12 to the cellular TC receptor. TC II deficiency is a very rare disease and is life-threatening if left untreated. It is an Autosomal recessive disease and needs lifelong treatment. The clinical presentations are variable, started at early infancy, and sometimes mimic severe combined immunodeficiency or acute leukemia. It includes failure to thrive, diarrhea, anemia and or pancytopenia, hypotonia, developmental delay, and recurrent infection. Diagnosis of TC II deficiency is suspected based on clinical presentations with megaloblastic anemia, the elevation of plasma homocysteine, and urine methylmalonic acid level with a normal vitamin B12 and folate level. Molecular analysis of the TCN 2 gene is needed for confirmation of the diagnosis. Case Presentation: We present a case of 2 years old Saudi boy who was admitted to the hospital with a history of fever, recurrent chest infection, failure to thrive with diarrhea, and hypotonia, and his complete blood counts showed Pancytopenia. Though, normal vitamin B12 level and folate level, homocysteine, and urine methylmalonic acid lever were elevated. Peripheral smear and bone marrow aspiration and biopsy revealed Hypersegmented neutrophils and megaloblastic change.

Transcobalamin (TC) is a carrier protein and it delivers vitamin B12 to the cellular TC receptor. TC II deficiency is a very rare disease and is life-threatening if left untreated. It is an Autosomal recessive disease and needs lifelong treatment. The clinical presentations are variable, started at early infancy, and sometimes mimic severe combined immunodeficiency or acute leukemia. It includes failure to thrive, diarrhea, anemia and or pancytopenia, hypotonia, developmental delay, and recurrent infection. Diagnosis of TC II deficiency is suspected based on clinical presentations with megaloblastic anemia, the elevation of plasma homocysteine, and urine methylmalonic acid level with a normal level of vitamin B12 and folate. Molecular analysis of the TCN 2 gene is needed for confirmation of the diagnosis. We present a case of 2 years old Saudi boy who was admitted to the hospital with a history of fever, recurrent chest infection, failure to thrive with diarrhea, and hypotonia, and his complete blood counts showed Pancytopenia. Though, normal vitamin B12 level and folate level, homocysteine, and urine methylmalonic acid lever were elevated. Peripheral smear and bone marrow aspiration and biopsy revealed Hypersegmented neutrophils and megaloblastic change.