Journal of the Association of Genetic Technologists最新文献

Objectives: 16p11.2 deletion syndrome is a rare genetic abnormality that affects an individual's cognitive abilities. 16p11.2 deletion syndrome is characterized by a loss of region 11.2 on chromosome 16, which includes several genes with various functions. Numerous genes linked to this loss are essential for brain function and neurodevelopment. Notably, genes associated with neuronal development, synaptic function, and brain connection have been found inside the deleted region, including KIF22, TAOK2, and ALDOA, as well as approximately 22 to 25 other additional genes. The diverse clinical presentations noted in patients with 16p11.2 deletion syndrome can be ascribed to the intricate interactions among these mutated genes and their influence on multiple cellular processes. The 16p11.2 deletion syndrome is not observable by conventional cytogenetics. Chromosomal microarray studies are recommended to detect this 16p11.2 deletion.

Objectives: Lenalidomide, a derivative of thalidomide, is a type of immunomodulatory drug (IMiD) that has been standard therapy for multiple myeloma (MM) and other hematologic malignancies for almost two decades. The success of these drugs in MM has contributed to increased survival of patients and, as a result, patients are at risk for a secondary primary malignancy (SPM), some of which occur as a result of treatment for MM. MM patients have an increased risk for acute myeloid leukemia (AML) and Kaposi sarcoma. In addition, treatment with IMiDs is also associated with an increased risk for myelodysplastic neoplasms (MDS), squamous cell carcinoma of the skin, and, less frequently, acute lymphoblastic leukemia (ALL). We present a case of an elderly male with MM and multiple subsequent skin cancers, who presented with pancytopenia and was diagnosed with B-lymphoblastic leukemia (B-ALL) after 10 years of maintenance lenalidomide therapy.

Objectives: Identifying therapy-related AML (t-AML) of newly diagnosed acute leukemias is of great interest. Development of t-AML can occur after cytotoxic chemotherapy and/or radiation. We report a case of t-AML with CBFB::MYH11 fusion in a patient with a distant history of treated stage IIIB nodular sclerosing Hodgkin's lymphoma. We present the clinical course of the patient and the methods used to detect and monitor the rearrangement. Core binding factor AML (CBF-AML) after exposure to treatment is considered to be a good prognostic marker. The identification of these favorable AML subtypes such as CBF-AML highlights the importance of identifying genetic alterations, especially with increasing incidences of t-AML due to changes in choice of treatment and prognosis.

Objectives: Ring chromosome 14 is a rarely observed chromosomal abnormality characterized by a circular, ring-like appearance in one or both copies of chromosome 14. Ring chromosome 14 syndrome (OMIM #616606) is marked by global developmental delays, drug-resistant epilepsy, microcephaly, and ocular abnormalities. To date, fewer than 100 cases of ring chromosome 14 syndrome have been described in the medical literature. We describe a case of ring chromosome 14 and its clinical presentation in a 10-year-old female, adding to the literature about this rare condition.

Objectives: Fluorescent in situ hybridization has been the definitive modality in testing for overexpression of the Human Epidermal Growth Factor Receptor 2 (HER2) for decades to guide the appropriate treatment for cancer patients. In more recent years innovation and new techniques have been developed to supplant or even replace FISH as a standard method for biomarker testing. Alternative testing methods such polymerase chain reaction (PCR), next-generation sequencing (NGS), and other in situ hybridization (ISH)-derived techniques such as chromogenic-ISH (CISH) have been shown in multiple publications to have high concordance with FISH in addition to advantages in economics, logistics and practicality to the point where CISH and derived methods appear to have eclipsed FISH as a testing method of choice after immunohistochemistry (IHC). This review assesses the status of FISH compared to other diagnostic techniques such as IHC, CISH, and less common and/or experimental methods. Also addressed are the updates to the guidelines from the American Society of Clinical Oncology (ASCO), College of American Pathologists (CAP), and National Comprehensive Cancer Network (NCCN) regarding FISH and IHC for HER2 testing with the updates reducing the number of equivocal diagnoses in the latest iteration. Though our findings show a constantly changing technological landscape, FISH remains an important primary tool to guide medical treatment and as a solid foundation to build upon for innovation in cancer research.

Objectives: Patients with Fanconi Anemia (FA) have an increased risk of developing myeloid malignancies, which often precede the diagnosis of FA. We describe a patient with non-specific clinical findings diagnosed with myelodysplastic syndrome (MDS) at 17 years of age. A pathogenic SF3B1 alteration was identified and prompted evaluation for a bone marrow failure syndrome. Chromosomal breakage testing demonstrated an increase in breakage and radial formation; a targeted FA molecular panel identified variants of unknown significance in FANCB and FANCM. To date, reports of pediatric patients, with or without a co-morbid diagnosis of FA, diagnosed with MDS with SF3B1 alteration are rare. We describe a patient with FA diagnosed with MDS with ring sideroblasts and multilineage dysplasia (MDS-RS-MLD, WHO revised 4th edition) with an associated SF3B1 alteration and discuss the new classifications of this entity. In addition, as the knowledge around FA grows, so too does the knowledge about genes associated with FA. We present a novel variant of unknown significance in FANCB, to add to the growing body of literature about genetic alterations identified in individuals with a clinical picture most in keeping with FA.

Objectives: The ribosomal protein S14 (RPS14) gene located at 5q33 codes for a protein involved in ribosomal biogenesis. The RPS14 gene has a length of 5.9 kb of DNA comprising 5 exons and 4 introns. It is possible that RPS14 is involved in the formation of pre-RNA 18s, an intermediate RNA that serves for the formation of the 40S small subunit of the ribosome. RPS14 haploinsufficiency (HI) produces alterations in intermediate RNA levels (pre-RNA 30S/18SE/18S), which are found in del(5q) MDS. In addition, RPS14 haploinsufficiency results in the formation of the MDM2 (double minute mouse E3 ubiquitin ligase)-RP (ribosomal protein) complex that prevents the MDM2-p53 interaction, generating an accumulation of p53 levels. This accumulation produces cell cycle arrest, impaired DNA repair, senescence, and apoptosis. RPS14 haploinsufficiency has been seen in MDS. Altered expression levels of RPS14 have also been reported in glioma, colorectal cancer, hepatocellular carcinoma, breast cancer, renal cell carcinoma, and primary myelofibrosis.

Objectives: Myelodysplastic syndrome with excess blasts-2 (MDS-EB-2) primarily affects adults older than 50 years and confers a worse prognosis with a higher risk of transformation to acute myeloid leukemia (AML) compared to myelodysplastic syndrome (MDS) and MDS with excess blasts-1 (MDS-EB-1). In ordering diagnostic studies for MDS, cytogenetic and genomic studies are vital as they have significant clinical and prognostic implications for the patient. We present a case of a 71-year-old male diagnosed with MDS-EB-2 with a pathogenic loss-of-function TP53 variant and discuss presentation, pathogenesis, and the importance of thorough diagnostic testing through multiple modalities to accurately diagnose and subtype MDS. In addition, we explore a historical overview of the diagnostic criteria of MDS-EB-2 and how it has changed over time from the World Health Organization (WHO) 4th edition in 2008, the WHO revised 4th edition in 2017, and the upcoming WHO 5th edition and International Consensus Classification (ICC) for 2022.

Objectives: We present a case study of a 73-year-old female with a history of pancytopenia. The bone marrow core biopsy was suggestive of a myelodysplastic syndrome, unspecified (MDS-U). Chromosomal analysis of the bone marrow revealed an abnormal karyotype including gain of chromosomes 1, 4, 6, 8, 9, 19, and 20 in addition to loss of chromosomes 11, 13, 15, 16, 17, and 22. Also, additional material of unknown origin was found on 3q, 5p, 9p, 11p, 13p, 14p, and 15p; there were two copies of 19p, a deletion of 8q, and numerous unidentified rings and markers were present. This was characterized as: 75~77,XXX,+1,der(1;6)(p10;p10),add(3)(q27),+4,add(5)(p15.1),+6,+8,del(8)(q24.1),+add(9)(p24),-11,add (11) (p13),-13,add(13)(p10),add(14)(p11.2),-15,add(15)(p11.2), -16,-17,+19,add(19)(p13.3)x2,+20,-22, +0~4r,+4~10mar[cp11]/46,XX[8]. The cytogenetic analysis correlates with the concurrent FISH study which was positive for additional signals of EVI1(3q26.2), TAS2R1 (5p15.31), EGR1 (5q31.2), RELN (7q22), TES (7q31) RUNX1T1 (8q21.3), ABL1 (9q34), KMT2A (11q23), PML (15q24.1), CBFB (16q22), RARA (17q21), PTPRT (20q12), MYBL2 (20q13.12), RUNX1 (21q22.12) and BCR (22q11.2). Hyperdiploid karyotypes within the context of complex structural abnormalities are rare events usually associated with a poor prognosis in MDS.

Objectives: Objectives Disorders of sex development(DSD)can result in discordance between the chromosomal and anatomicand/orphenotypic sex of a patient. Reporting patients with uncommon karyotypes associated with DSD is important for clinical comparison of developmental outcomes, and management. Methods We describe three female patients with karyotypes resulting in DSD and the use of a combination of chromosomes and FISH techniques to identify potential causes. Results The first patient was mosaic for idic(Y) that was negative for SRY by FISH. The second patient had idic(Y) that was positive for SRY by FISH. The third patient had an unbalanced translocation between the X chromosome and chromosome 2 [der(2)(X;2)] and XY. These three patients illustrate three different genetic mechanisms underlying DSD. Conclusion Our findings expand the list of abnormal karyotypes that can be associated with DSD and highlight the importance of SRY and DAX1 in phenotypic and functional sexual development.