First Report of a Derivative Chromosome 13 with a Duplicated 11p15 Locus Associated with Silver-Russell Syndrome.

Silver-Russell Syndrome (SRS) is a disorder that is primarily characterised by intrauterine growth restriction which may occur asymmetrically or in whole, leading to a fetus being small relative to its gestational age. We present a female infant (proband) born in 2018 at a tertiary hospital in Muscat, Oman, with severe congenital anomalies. The proband carried a >25Mb duplication of the chromosomal 11p15-11pter locus of chromosome 13; creating a derivative chromosome 13 (der[13]) and was reported as 46,XX,der(13)add(11p15-11pter).

Importance of FISH combined with Morphology, Immunophenotype and Cytogenetic Analysis of Childhood/ Adult Acute Lymphoblastic Leukemia in Omani Patients.

Genetic changes associated with acute lymphoblastic leukemia (ALL) provide very important diagnostic and prognostic information with a direct impact on patient management. Detection of chromosome abnormalities by conventional cytogenetics combined with fluorescence in situ hybridization (FISH) play a very significant role in assessing risk stratification. Identification of specific chromosome abnormalities has led to the recognition of genetic subgroups based on reciprocal translocations, deletions and modal number in B or T-cell ALL.

Simplified method for the collection, storage, and comet assay analysis of DNA damage in whole blood.

Single-cell gel electrophoresis (comet assay) is one of the most common methods used to measure oxidatively damaged DNA in peripheral blood mononuclear cells (PBMC), as a biomarker of oxidative stress in vivo. However, storage, extraction, and assay workup of blood samples are associated with a risk of artifactual formation of damage. Previous reports using this approach to study DNA damage in PBMC have, for the most part, required the isolation of PBMC before immediate analysis or freezing in cryopreservative.

Incidence of chromosome abnormalities in the Sultanate of Oman.

Objectives: To evaluate the cytogenetic findings in Omani children referred for suspected chromosomal anomalies that caused a variety of clinical disorders. Secondly, to study the frequency of chromosomal abnormalities in these patients and to compare our results with those reported elsewhere.

Methods: We performed chromosomal analysis on 1800 consecutive pediatric patients referred to the Cytogenetics section between June 1999 and May 2004 at Central Public Health Laboratories, Sultanate of Oman.