Development of a Quantitative Multiplex PCR to Detect Three Common Alpha Thalassemia Deletions.

Alpha thalassemia is an autosomal recessive genetic disorder with a high prevalence in the Middle East. The severe form of alpha-thalassemia is incompatible with life and can cause significant obstetric complications in the mother. Therefore, it is important to determine the genotype in parents who have a chance of having a fetus with one of the severe forms of this disease. A total of 112 samples that were previously analyzed for common alpha thalassemia mutations in Iran were used in this study. A new multiplex PCR including quantitative polymerase chain reaction to amplify the homologous regions of the alpha-globin gene cluster and fluorescent gap PCR was designed to identify -α3.7, -α4.2, --MED deletions. The ROC curve was used to determine the optimum cutoff points. Statistical analysis showed that there is a significant difference between the peak height ratios for different genotypes. The peak corresponding to the 297 bp fragment resulting from the amplification of the allele with MED-I deletion was detected in all the samples with this deletion. Different cutoffs for a range of sensitivities and specificities were determined by the ROC curve. The suggested method can identify three common large deletions in the alpha-globin gene cluster. A study with a larger sample size can provide more accurate information about the sensitivity and specificity of this test.

Molecular insight of dyskeratosis congenita: Defects in telomere length homeostasis.

BACKGROUND: Dyskeratosis congenita (DC) is a rare disease and is a heterogenous disorder, with its inheritance patterns as autosomal dominant, autosomal recessive, and X-linked recessive. This disorder occurs due to faulty maintenance of telomeres in stem cells. This congenital condition is diagnosed with three symptoms: oral leukoplakia, nail dystrophy, and abnormal skin pigmentation. However, because it has a wide range of symptoms, it may have phenotypes similar to other diseases. For this reason, it is necessary to use methods of measuring the Telomere Length (TL) and determining the shortness of the telomere in these patients so that it can be distinguished from other diseases. Today, the Next Generation Sequencing technique accurately detects mutations in the target genes. AIM: This work aims to review and summarize how each of the DC genes is involved in TL, and how to diagnose and differentiate the disease using clinical signs and methods to measure TL. It also offers treatments for DC patients, such as Hematopoietic Stem Cell Transplantation and Androgen therapy. RELEVANCE FOR PATIENTS: In DC patients, the genes involved in telomere homeostasis are mutated. Because these patients may have an overlapping phenotype with other diseases, it is best to perform whole-exome sequencing after genetics counseling to find the relevant mutation. As DC is a multi-systemic disease, we need to monitor patients frequently through annual lung function tests, ultrasounds, gynecological examinations, and skin examinations.