Deletions in the 17q chromosomal region and their influence on the clonal cytogenetic evolution of recurrent meningiomas

Abstract Prefertilization mechanisms influencing selfing rates are thought to be absent in conifers. Outcrossing in conifers is promoted via an embryo-lethal system, but the genetic mechanism is poorly understood. This study is the first experimental profile of the genetic mechanism promoting outcrossing in conifers. Molecular dissection of a Pinus taeda L. selfed pedigree detected a chromosomal region identified as PtTX3020-RPtest9. Within this region, a semilethal factor was tightly linked (r = 0.0076) to a polymorphic expressed sequence tag (EST). The linkage group flanking the lethal factor showed strong heterozygote advantage. Using genotypic frequencies for the linkage group, three hypotheses about the semilethal factor could be tested: (1) the presence of a balanced lethal system, i.e., a lethal factor present in each of the two marker intervals; (2) gametic selection operative prior to fertilization; and (3) a stage-specific lethal factor. Selection acted via the embryo-lethal system. No support for a genetic mechanism operating prior to fertilization was found. The semilethal factor exerted no effect after embryo maturity. The genetic mechanism promoting outcrossing in P. taeda L. appears to have a balancing selection system due to either pseudo-overdominance or true overdominance.

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Germline variant in REXO2 is a novel candidate gene in familial pheochromocytoma

Genetics Research ◽

10.1017/s0016672320000038 ◽

2020 ◽

Vol 102 ◽

Cited By ~ 1

Author(s):

Yael Laitman ◽

Shay Tzur ◽

Ruben Attali ◽

Amit Tirosh ◽

Eitan Friedman

Keyword(s):

Allelic Imbalance ◽

Chromosomal Region ◽

Cancer Susceptibility ◽

Functional Studies ◽

Cancer Susceptibility Genes ◽

Whole Exome ◽

Familial Pheochromocytoma ◽

The Family ◽

Recombination Processes

Abstract Pheochromocytoma (PCC) is a rare, mostly benign tumour of the adrenal medulla. Hereditary PCC accounts for ~35% of cases and has been associated with germline mutations in several cancer susceptibility genes (e.g., KIF1B, SDHB, VHL, SDHD, RET). We performed whole-exome sequencing in a family with four PCC-affected patients in two consecutive generations and identified a potential novel candidate pathogenic variant in the REXO2 gene that affects splicing (c.531-1G>T (NM 015523.3)), which co-segregated with the phenotype in the family. REXO2 encodes for RNA exonuclease 2 protein and localizes to 11q23, a chromosomal region displaying allelic imbalance in PCC. REXO2 protein has been associated with DNA repair, replication and recombination processes and thus its inactivation may contribute to tumorigenesis. While the study suggests that this novel REXO2 gene variant underlies PCC in this family, additional functional studies are required in order to establish the putative role of the REXO2 gene in PCC predisposition.

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Clinical characteristics of Polish patients with molecularly confirmed Mowat-Wilson syndrome

Journal of Applied Genetics ◽

10.1007/s13353-021-00636-1 ◽

2021 ◽

Author(s):

Aleksandra Jakubiak ◽

Krzysztof Szczałuba ◽

Magdalena Badura-Stronka ◽

Anna Kutkowska-Kaźmierczak ◽

Anna Jakubiuk-Tomaszuk ◽

...

Keyword(s):

Intellectual Disability ◽

Congenital Anomalies ◽

Chromosomal Region ◽

Neurodevelopmental Disorder ◽

Hirschsprung Disease ◽

Psychomotor Retardation ◽

Facial Features ◽

Dysmorphic Features ◽

Pathogenic Variants ◽

Intragenic Deletions

AbstractMowat-Wilson syndrome is a rare neurodevelopmental disorder caused by pathogenic variants in the ZEB2 gene, intragenic deletions of the ZEB2 gene, and microdeletions in the critical chromosomal region 2q22-23, where the ZEB2 gene is located. Mowat-Wilson syndrome is characterized by typical facial features that change with the age, severe developmental delay with intellectual disability, and multiple congenital abnormalities. The authors describe the clinical and genetic aspects of 28th patients with Mowat-Wilson syndrome diagnosed in Poland. Characteristic dysmorphic features, psychomotor retardation, intellectual disability, and congenital anomalies were present in all cases. The incidence of most common congenital anomalies (heart defect, Hirschsprung disease, brain defects) was similar to presented in literature. Epilepsy was less common compared to previously reported cases. Although the spectrum of disorders in patients with Mowat-Wilson syndrome is wide, knowledge of characteristic dysmorphic features awareness of accompanying abnormalities, especially intellectual disability, improves detection of the syndrome.

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A possible susceptibility locus for bipolar affective disorder in chromosomal region 10q25–q26

Molecular Psychiatry ◽

10.1038/sj.mp.4000864 ◽

2001 ◽

Vol 6 (3) ◽

pp. 342-349 ◽

Cited By ~ 41

Author(s):

S Cichon ◽

G Schmidt-Wolf ◽

J Schumacher ◽

D J Müller ◽

M Hürter ◽

...

Keyword(s):

Affective Disorder ◽

Chromosomal Region ◽

Bipolar Affective Disorder ◽

Susceptibility Locus

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Analysis of the Functions of Recombination-Related Genes in the Generation of Large Chromosomal Deletions by Loop-Out Recombination in Aspergillus oryzae

Eukaryotic Cell ◽

10.1128/ec.05208-11 ◽

2012 ◽

Vol 11 (4) ◽

pp. 507-517 ◽

Cited By ~ 7

Author(s):

Tadashi Takahashi ◽

Masahiro Ogawa ◽

Yasuji Koyama

Keyword(s):

Aspergillus Oryzae ◽

Chromosomal Region ◽

Centromeric Region ◽

Chromosome 8 ◽

Telomeric Region ◽

Dna Double Strand Breaks ◽

Chromosomal Structure ◽

Content Type ◽

Strand Breaks ◽

Chromosomal Deletions

ABSTRACT Loop-out-type recombination is a type of intrachromosomal recombination followed by the excision of a chromosomal region. The detailed mechanism underlying this recombination and the genes involved in loop-out recombination remain unknown. In the present study, we investigated the functions of ku70 , ligD , rad52 , rad54 , and rdh54 in the construction of large chromosomal deletions via loop-out recombination and the effect of the position of the targeted chromosomal region on the efficiency of loop-out recombination in Aspergillus oryzae . The efficiency of generation of large chromosomal deletions in the near-telomeric region of chromosome 3, including the aflatoxin gene cluster, was compared with that in the near-centromeric region of chromosome 8, including the tannase gene. In the Δ ku70 and Δ ku70-rdh54 strains, only precise loop-out recombination occurred in the near-telomeric region. In contrast, in the Δ ligD , Δ ku70-rad52 , and Δ ku70-rad54 strains, unintended chromosomal deletions by illegitimate loop-out recombination occurred in the near-telomeric region. In addition, large chromosomal deletions via loop-out recombination were efficiently achieved in the near-telomeric region, but barely achieved in the near-centromeric region, in the Δ ku70 strain. Induction of DNA double-strand breaks by I-SceI endonuclease facilitated large chromosomal deletions in the near-centromeric region. These results indicate that ligD , rad52 , and rad54 play a role in the generation of large chromosomal deletions via precise loop-out-type recombination in the near-telomeric region and that loop-out recombination between distant sites is restricted in the near-centromeric region by chromosomal structure.

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