Detection of Mutations in Argentine Retinoblastoma Patients by Segregation of Polymorphisms, Exon Analysis and Cytogenetic Test

Dalamon, Viviana Karina; Surace, Ezequiel; Borelina, Daniel; Ziembar, María I.; Esperante, Sebastián; Francipane, Liliana; Dávila, María Teresa García de; Parma, Diana Lidia; Szijan, Irene

doi:10.1159/000055690

Cited by 6 publications

(5 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The deoxyribonucleic acid (DNA) was obtained from peripheral blood leukocytes using the cetyltrimethylammonium bromide (CTAB) method, and from paraffin-embedded tumors by treatment with proteinase K. 9 Segregation analysis of six polymorphic loci within RB1 gene included: (i) three intragenic restriction fragment length polymorphisms (RFLPs): BamHI, XbaI and Tth111I (introns 1, 17 and 24), and (ii) three microsatellites: RBi2, RBi4 and RB1.20 (introns 2, 4 and 20). 10,11 The RFLPs amplified fragments were digested with the appropriate restriction enzyme and visualized in a 2% agarose gel by etidium bromide staining.…”

Section: Dna Isolation and Genotyping Of Polymorphic Locimentioning

confidence: 99%

See 1 more Smart Citation

Spectrum ofRB1Mutations in Argentine Patients: 20-years Experience in the Molecular Diagnosis of Retinoblastoma

Ottaviani

Parma

Giliberto

et al. 2013

Ophthalmic Genetics

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Dna Isolation and Genotyping Of Polymorphic Locimentioning

confidence: 99%

“…Some of these results were already published. 9,10,12,13 Mutations were widely distributed throughout the RB1 gene and no hot spots were found. Most of the mutations had occurred de novo and differ from one patient to another.…”

Section: Mutational Analysismentioning

confidence: 99%

Spectrum ofRB1Mutations in Argentine Patients: 20-years Experience in the Molecular Diagnosis of Retinoblastoma

Ottaviani

Parma

Giliberto

et al. 2013

Ophthalmic Genetics

Self Cite

View full text Add to dashboard Cite

show abstract

“…El análisis molecular fue informativo en 18 familias de las 34 incluidas en el estudio (53%) (tabla I), el 56% con Rb bilateral y el 44% con Rb unilateral (10)(11)(12)(13)(14). En 15 de ellas fue posible identificar si el alelo mutado era el paterno (en 6) o el materno (en 9).…”

Section: Resultsunclassified

“…Todos los casos fueron esporádicos, excepto la familia 1, que presentó padre (1) e hija (1´) con Rb. En total, se analizaron 130 muestras de ADN de leucocitos de sangre periférica, tumores y vellosidades coriónicas, por ensayos de Biología Molecular indirectos y directos como Southern blot (10), segregación de polimorfismos (11)(12)(13), PCR-heteroduplex y secuenciación (10,14) …”

Section: Sujetos Materials Y Métodosunclassified

Importancia de los estudios de biología molecular en el asesoramiento genético de familias argentinas con retinoblastoma

Parma

Dalamon

Fernández

et al. 2009

Arch Soc Esp Oftalmol

View full text Add to dashboard Cite

RESUMENObjetivo: Evaluar la importancia de la detección de mutaciones del gen RB1 en el asesoramiento gené-tico de las familias argentinas con retinoblastoma. Métodos: Se incluyeron en este estudio 34 familias argentinas con Retinoblastoma (Rb) bilateral y unilateral. Se analizaron 130 muestras de ADN de leucocitos, tumores y vellosidades coriónicas, por ensayos de Biología Molecular indirectos y directos, como Southern blot, segregación de los polimorfismos BamHI, Rbi4, XbaI y Rb 1.20 (PCR-RFLP, PCR-STR), PCR-heteroduplex y secuenciación del gen RB1. Resultados: El análisis molecular fue informativo en 18 familias de las 34 incluidas en el estudio (53%), el 56% con Rb bilateral y el 44% con Rb unilateral. Se contó con muestras de ADN tumoral de 11 pacientes que se estudiaron para detectar pér-dida de heterocigosidad (LOH), que posibilitó identificar el alelo RB1 mutado en 9 pacientes (82%). Cuando no se analizaron las muestras tumorales, ABSTRACTObjective: Evaluate the relevance of RB1 mutations detection in the genetic counselling of Argentine retinoblastoma families. Methods: We included in this study 34 Argentine families with bilateral and unilateral Retinoblastoma (Rb). 130 DNA samples from leukocytes, tumors and chorionic villus were analyzed by indirect and direct molecular biology assays like Southern blot, segregation of polymorphisms BamHI, Rbi4, XbaI y Rb 1.20 (PCR-RFLP, PCR-STR), PCR-heteroduplex and sequencing of RB1 gene. Results: Molecular biology analysis was informative in 18 out of 34 families studied (53%), 56% with bilateral and 44% with unilateral Rb. DNA tumor samples of 11 patients were available and could be studied by loss of heterozygosity (LOH) detection, that allowed us to identify the mutated RB1 allele in 9 (82%) patients. When tumor samples were not analized, the studies were informative only in 9 out of 23 patients (39%); we used direct mutation

show abstract

“…Inactivation of both copies of the RB1 gene results in retinoblastoma [Knudson, 1971]. The spectrum of causative mutations ranges from large deletions to single base substitutions, with over 400 mutations in the RB1 gene having been reported to date [Alonso et al, 2001;Ata-ur-Rasheed et al, 2002;Blanquet et al, 1993Blanquet et al, , 1994Blanquet et al, , 1995Cowell and Cragg, 1996;Cowell et al, 1994;Dalamon et al, 2001;Houdayer et al, 2004;Jakubowska et al, 2001;Kiran et al, 2003;Kloss et al, 1991;Kumaramanickavel et al, 2003;Liu et al, 1995;Lohmann et al, 1992Lohmann et al, , 1994aLohmann et al, , 1994bLohmann et al, , 1996Lohmann et al, , 1997Richter et al, 2003;Yilmaz et al, 1998] (www.d-lohmann.de/Rb/mutations.html). The majority of these mutations disrupt protein function, i.e., nonsense and frameshift mutations, which account for about 76% of the mutations, followed by splice site mutations (15%), missense mutations (6%), in-frame deletions (2%), and mutations in the promoter region (1%).…”

Section: Introductionmentioning

confidence: 99%

Conservation of theRB1gene in human and primates

et al. 2005

View full text Add to dashboard Cite

Mutations in the RB1 gene are associated with retinoblastoma, which has served as an important model for understanding hereditary predisposition to cancer. Despite the great scrutiny that RB1 has enjoyed as the prototypical tumor suppressor gene, it has never been the object of a comprehensive survey of sequence variation in diverse human populations and primates. Therefore, we analyzed the coding (2,787 bp) and adjacent intronic and untranslated (7,313 bp) sequences of RB1 in 137 individuals from a wide range of ethnicities, including 19 Asian Indian hereditary retinoblastoma cases, and five primate species. Aside from nine apparently disease-associated mutations, 52 variants were identified. They included six singleton, coding variants that comprised five amino acid replacements and one silent site. Nucleotide diversity of the coding region (pi=0.0763+/-1.35 x 10(-4)) was 52 times lower than that of the noncoding regions (pi=3.93+/-5.26 x 10(-4)), indicative of significant sequence conservation. The occurrence of purifying selection was corroborated by phylogeny-based maximum likelihood analysis of the RB1 sequences of human and five primates, which yielded an estimated ratio of replacement to silent substitutions (omega) of 0.095 across all lineages. RB1 displayed extensive linkage disequilibrium over 174 kb, and only four unique recombination events, two in Africa and one each in Europe and Southwest Asia, were observed. Using a parsimony approach, 15 haplotypes could be inferred. Ten were found in Africa, though only 12.4% of the 274 chromosomes screened were of African origin. In non-Africans, a single haplotype accounted for from 63 to 84% of all chromosomes, most likely the consequence of natural selection and a significant bottleneck in effective population size during the colonization of the non-African continents.

show abstract

Detection of Mutations in Argentine Retinoblastoma Patients by Segregation of Polymorphisms, Exon Analysis and Cytogenetic Test

Cited by 6 publications

References 7 publications

Spectrum ofRB1Mutations in Argentine Patients: 20-years Experience in the Molecular Diagnosis of Retinoblastoma

Spectrum ofRB1Mutations in Argentine Patients: 20-years Experience in the Molecular Diagnosis of Retinoblastoma

Importancia de los estudios de biología molecular en el asesoramiento genético de familias argentinas con retinoblastoma

Conservation of theRB1gene in human and primates

Contact Info

Product

Resources

About