scholarly journals Dynamic mutations pose unique challenges for the molecular diagnostics laboratory

1996 ◽  
Vol 42 (10) ◽  
pp. 1582-1588 ◽  
Author(s):  
R C McGlennen
Keyword(s):  
Polymerase Chain Reaction ◽  
Molecular Diagnostics ◽  
Diagnostic Tests ◽  
Trinucleotide Repeat ◽  
Molecular Testing ◽  
Ethical Challenges ◽  
Clinical Context ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Dynamic Mutations

Abstract Routine clinical molecular testing of diseases associated with unstable or dynamic trinucleotide repeat syndromes poses unique technical, medical, and ethical challenges to the laboratory. Although the pathophysiology of these disorders is to date still largely undefined, the uniformity of their genetics has led to the development of highly informative diagnostic tests. In general, amplification techniques, such as the polymerase chain reaction (PCR), are used to determine the size of alleles within the genes linked to these disorders. Technically, these assays require empirical optimization so that the PCR reactions are both robust and reproducible, and occasionally other methods must be used to confirm diagnoses. Beyond execution of the test, however, the molecular diagnostics laboratory needs also to be fundamentally involved in the process of interpreting these tests in the correct clinical context and in setting policy as to how these data are presented to patients.

scholarly journals 5′ UTR CGG repeat expansion in GIPC1 is associated with oculopharyngodistal myopathy

Brain ◽  
2020 ◽  
Author(s):  
Jianying Xi ◽  
Xilu Wang ◽  
Dongyue Yue ◽  
Tonghai Dou ◽  
Qunfeng Wu ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Trinucleotide Repeat ◽  
Late Onset ◽  
Age At Onset ◽  
Large Family ◽  
Repeat Expansion ◽  
Chain Reaction ◽  
Cgg Repeat ◽  
Sporadic Cases ◽  
Polymerase Chain

Abstract Oculopharyngodistal myopathy is a late-onset degenerative muscle disorder characterized by ptosis and weakness of the facial, pharyngeal, and distal limb muscles. A recent report suggested a non-coding trinucleotide repeat expansion in LRP12 to be associated with the disease. Here we report a genetic study in a Chinese cohort of 41 patients with the clinical diagnosis of oculopharyngodistal myopathy (21 cases from seven families and 20 sporadic cases). In a large family with 12 affected individuals, combined haplotype and linkage analysis revealed a maximum two-point logarithm of the odds (LOD) score of 3.3 in chromosomal region chr19p13.11-p13.2 and narrowed the candidate region to an interval of 4.5 Mb. Using a comprehensive strategy combining whole-exome sequencing, long-read sequencing, repeat-primed polymerase chain reaction and GC-rich polymerase chain reaction, we identified an abnormal CGG repeat expansion in the 5′ UTR of the GIPC1 gene that co-segregated with disease. Overall, the repeat expansion in GIPC1 was identified in 51.9% independent pedigrees (4/7 families and 10/20 sporadic cases), while the repeat expansion in LRP12 was only identified in one sporadic case (3.7%) in our cohort. The number of CGG repeats was <30 in controls but >60 in affected individuals. There was a slight correlation between repeat size and the age at onset. Both repeat expansion and retraction were observed during transmission but somatic instability was not evident. These results further support that non-coding CGG repeat expansion plays an essential role in the pathogenesis of oculopharyngodistal myopathy.

Mantle Cell Lymphoma

1999 ◽  
Vol 123 (12) ◽  
pp. 1182-1188 ◽  
Author(s):  
Rebecca C. Hankin ◽  
Susan V. Hunter
Keyword(s):  
Polymerase Chain Reaction ◽  
B Cell ◽  
Mantle Cell Lymphoma ◽  
Diagnostic Tests ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Molecular Diagnostic ◽  
Chain Reaction ◽  
Mantle Cell ◽  
Polymerase Chain

Abstract Objective.—This article summarizes the most useful ancillary immunohistochemical and molecular assays for use in the diagnosis of mantle cell lymphoma. Data Sources.—The English language literature was surveyed, with an emphasis on recent publications, for articles presenting key advances in the molecular characterization of mantle cell lymphomas and for series of cases testing the utility of molecular diagnostic tests. The authors' series of 26 small B-cell lymphomas, analyzed for the cyclin D1 protein by paraffin immunohistochemistry and for t(11;14) by polymerase chain reaction, is included. Conclusions.—Mantle cell lymphoma, a B-cell lymphoma now recognized in the 1994 Revised European-American Classification of Lymphoid Neoplasms (REAL) classification, is a relatively aggressive lymphoma with a poor prognosis. Its characteristic t(11;14)(q13;q32) translocation has a role in oncogenesis and has been exploited for molecular diagnostic tests, but these tests vary in sensitivity, specificity, and ease of use. Improved immunohistochemical tests are sufficient to confirm the diagnosis in most cases. Conventional cytogenetics and molecular diagnostic tests for t(11;14)—Southern blot and polymerase chain reaction analysis—may be helpful in selected cases, but are laborious or of limited sensitivity. Other methods, such as fluorescence in situ hybridization, need further development to provide faster, more sensitive diagnosis.

scholarly journals Current Avenues for COVID-19 Serology

2020 ◽  
Vol 56 (02) ◽  
pp. 087-090
Author(s):  
Saumya Srivastava ◽  
Vidhi Jain ◽  
Vijaya Lakshmi Nag ◽  
Sanjeev Misra ◽  
Kuldeep Singh
Keyword(s):  
Polymerase Chain Reaction ◽  
Gold Standard ◽  
Diagnostic Tests ◽  
Immune Status ◽  
Contact Tracing ◽  
Great Promise ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Diagnostic Assays ◽  
Polymerase Chain

AbstractDevelopment of rapid, reliable, and easy diagnostic tests with high-throughput is the need of the hour for laboratories combating the COVID-19 pandemic. While real-time polymerase chain reaction (RT-PCR) is the gold standard for diagnosing active infections, it is expensive and time-consuming. Serological diagnostic assays with a premise to aid rapid contact tracing, immune status determination, and identification of potential convalescent plasma donors hold great promise. Timely diagnosis, effective treatment, and future prevention are key to management of COVID-19.

scholarly journals Solar thermal polymerase chain reaction for smartphone-assisted molecular diagnostics

2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Li Jiang ◽  
Matthew Mancuso ◽  
Zhengda Lu ◽  
Gunkut Akar ◽  
Ethel Cesarman ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Molecular Diagnostics ◽  
Solar Thermal ◽  
Chain Reaction ◽  
Polymerase Chain

scholarly journals Cutaneous Leishmaniasis of Lip and Role of Polymerase Chain Reaction: A Case Report

2020 ◽  
Vol 58 (227) ◽  
Author(s):  
Niraj Parajuli ◽  
Srijan Shrestha ◽  
Krishna Das Manandhar ◽  
Anup Bastola
Keyword(s):  
Polymerase Chain Reaction ◽  
Cutaneous Leishmaniasis ◽  
Leishmania Donovani ◽  
Polymerase Chain Reaction Test ◽  
Molecular Testing ◽  
Chain Reaction ◽  
Chain Reactions ◽  
Reaction Test ◽  
Polymerase Chain ◽  
Chain Reaction Test

The diagnosis of cutaneous leishmaniasis is mostly confirmed by the identification of parasitein a skin smear or biopsy. However, this method may not always be sensitive enough to detectthe disease when parasitic load is low. Molecular test such as polymerase chain reactions canbe useful in such circumstances. Here, we report a case of cutaneous leishmaniasis diagnosedby a polymerase chain reaction test when both smear and biopsy failed to confirm the diagnosis.A 17-years-old female from mountainous district of Nepal, presented with a crusted plaqueover the upper lip for a duration of 6 months. Both skin smear and biopsy from the lesionfailed to demonstrate Leishmania parasite but a polymerase chain reaction test was positivefor Leishmania donovani. This case emphasizes on the importance of molecular testing suchas polymerase chain reaction when commonly performed diagnostics test fails to supportconfirmation of clinical diagnosis.

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