Related Experiment Video
Updated: Jan 29, 2026

Spontaneous Murine Model of Anaplastic Thyroid Cancer
Published on: February 3, 2023
Clinicopathological Significance of Overall Frequency of Allelic Loss (OFAL) in Lesions Derived from Thyroid
Monika Migdalska-Sęk1, Karolina H Czarnecka2, Michał Kusiński3
1Department of Biomedicine and Genetics, Medical University of Lodz, Pomorska 251 St, 92-213, Lodz, Poland. monika.migdalska-sek@umed.lodz.pl.
Background:
Loss of heterozygosity (LOH) and microsatellite instability (MSI) are frequent molecular events in thyroid tumor etiopathogenesis occurring in several chromosomal critical areas, including 3p12-25.3, 7q21-31, 10q22-24, and 15q11-13, with loci of tumor suppressor genes.
Objective:
We evaluated the usefulness of LOH/MSI as a diagnostic/prognostic biomarker in lesions derived from thyroid follicular cells: follicular thyroid carcinoma (FTC); follicular adenoma (FA), papillary thyroid carcinoma (PTC), and nodular goiter (NG).
Methods:
We performed allelotyping (GeneMapper Software v. 4.0.) of ten microsatellite markers linked to the 1p31.2, 3p21.3, 3p24.2, 9p21.3, 11p15.5, and 16q22.1 region on DNA from 93 primary thyroid lesions then evaluated the LOH/MSI frequency and overall frequency of allelic loss (OFAL).
Results:
We found regions with significantly increased frequency of LOH/MSI for specific histotypes: the 3p24.2 region for FA and 1p31.2 for FTC. LOH/MSI in 3p21.3 was significantly elevated in PTC and FTC. LOH/MSI in 3p21.3 was increased for small size tumors (T1a + T1b), tumors with no regional lymph node involvement (N0 + Nx), American Joint Committee on Cancer (AJCC) stage I tumors, and tumor diameter (Td) < 10 mm; in 1p31.2 for T2-3, N1, stage II-IV, and Td 10-30 mm; in 11p15.5 for T2-3, N1, stage II-IV, and Td > 30 mm. OFAL values were significantly higher in younger patients (< 40 years), in men, in those with T2-3 stage tumors, in those with increased Td, and in FA and FTC compared with NG and PTC.
Conclusions:
We confirmed the occurrence of LOH/MSI in 3p21.3 at an early stage of tumorigenesis and mapped 1p31.2 and 11p15.5 as characteristic for advanced-stage tumors. The results of our study may enable consideration of OFAL, defined as LOH/MSI coincidence in various chromosomal regions, as a tumor progression marker. OFAL values were significantly higher in follicular neoplasms (FA and FTC) than in PTC or NG; hence, increased OFAL values can be regarded as a characteristic feature of the follicular phenotype.
Related Concept Videos
Multiple Allele Traits
Loss of Carboxy Group as CO2: Decarboxylation of Malonic Acid Derivatives
Lethal Alleles
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Statistical Significance
Line Loss
Line loss impacts power delivery efficiency in a balanced three-phase circuit. The symmetry in such a circuit simplifies the...
Significance of Center of Mass

