1
|
Strong Hereditary Predispositions to Colorectal Cancer. Genes (Basel) 2022; 13:genes13122326. [PMID: 36553592 PMCID: PMC9777620 DOI: 10.3390/genes13122326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 12/14/2022] Open
Abstract
Cancer is one of the most common causes of death worldwide. A strong predisposition to cancer is generally only observed in colorectal cancer (5% of cases) and breast cancer (2% of cases). Colorectal cancer is the most common cancer with a strong genetic predisposition, but it includes dozens of various syndromes. This group includes familial adenomatous polyposis, attenuated familial adenomatous polyposis, MUTYH-associated polyposis, NTHL1-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis syndrome, Cowden syndrome, Lynch syndrome, and Muir-Torre syndrome. The common symptom of all these diseases is a very high risk of colorectal cancer, but depending on the condition, their course is different in terms of age and range of cancer occurrence. The rate of cancer development is determined by its conditioning genes, too. Hereditary predispositions to cancer of the intestine are a group of symptoms of heterogeneous diseases, and their proper diagnosis is crucial for the appropriate management of patients and their successful treatment. Mutations of specific genes cause strong colorectal cancer predispositions. Identifying mutations of predisposing genes will support proper diagnosis and application of appropriate screening programs to avoid malignant neoplasm.
Collapse
|
2
|
Germline mutations of the adenomatous polyposis coli (APC) gene in Algerian familial adenomatous polyposis cohort: first report. Mol Biol Rep 2022; 49:3823-3837. [PMID: 35142982 DOI: 10.1007/s11033-022-07228-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/03/2022] [Indexed: 10/19/2022]
Abstract
BACKGROUND Familial adenomatous polyposis (known also as classical or severe FAP) is a rare autosomal dominant colorectal cancer predisposition syndrome, characterized by the presence of hundreds to thousands of adenomatous polyps in the colon and rectum from an early age. In the absence of prophylactic surgery, colorectal cancer (CRC) is the inevitable consequence of FAP. The vast majority of FAP is caused by germline mutations in the adenomatous polyposis coli (APC) tumor suppressor gene (5q21). To date, most of the germline mutations in classical FAP result in truncation of the APC protein and 60% are mainly located within exon 15. MATERIAL AND METHODS In this first nationwide study, we investigated the clinical and genetic features of 52 unrelated Algerian FAP families. We screened by PCR-direct sequencing the entire exon 15 of APC gene in 50 families and two families have been analyzed by NGS using a cancer panel of 30 hereditary cancer genes. RESULTS Among 52 FAP index cases, 36 had 100 or more than 100 polyps, 37 had strong family history of FAP, 5 developed desmoids tumors, 15 had extra colonic manifestations and 21 had colorectal cancer. We detected 13 distinct germline mutations in 17 FAP families. Interestingly, 4 novel APC germline pathogenic variants never described before have been identified in our study. CONCLUSIONS The accumulating knowledge about the prevalence and nature of APC variants in Algerian population will contribute in the near future to the implementation of genetic testing and counseling for FAP patients.
Collapse
|
3
|
Abstract
Familial adenomatous polyposis (FAP) is a colorectal cancer predisposition syndrome with considerable genetic and phenotypic heterogeneity, defined by the development of multiple adenomas throughout the colorectum. FAP is caused either by monoallelic mutations in the adenomatous polyposis coli gene APC, or by biallelic germline mutations of MUTYH, this latter usually presenting with milder phenotype. The aim of the present study was to characterize the genotype and phenotype of Hungarian FAP patients. Mutation screening of 87 unrelated probands from FAP families (21 of them presented as the attenuated variant of the disease, showing <100 polyps) was performed using DNA sequencing and multiplex ligation-dependent probe amplification. Twenty-four different pathogenic mutations in APC were identified in 65 patients (75 %), including nine cases (37.5 %) with large genomic alterations. Twelve of the point mutations were novel. In addition, APC-negative samples were also tested for MUTYH mutations and we were able to identify biallelic pathogenic mutations in 23 % of these cases (5/22). Correlations between the localization of APC mutations and the clinical manifestations of the disease were observed, cases with a mutation in the codon 1200-1400 region showing earlier age of disease onset (p < 0.003). There were only a few, but definitive dissimilarities between APC- and MUTYH-associated FAP in our cohort: the age at onset of polyposis was significantly delayed for biallelic MUTYH mutation carriers as compared to patients with an APC mutation. Our data represent the first comprehensive study delineating the mutation spectra of both APC and MUTYH in Hungarian FAP families, and underscore the overlap between the clinical characteristics of APC- and MUTYH-associated phenotypes, necessitating a more appropriate clinical characterization of FAP families.
Collapse
|
4
|
Comparative‑high resolution melting: a novel method of simultaneous screening for small mutations and copy number variations. Hum Genet 2014; 133:535-45. [PMID: 24233542 PMCID: PMC3984413 DOI: 10.1007/s00439-013-1393-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/30/2013] [Indexed: 02/01/2023]
Abstract
Efficient and cost-effective screening for DNA sequence changes, both small mutations and copy number variations (CNVs), is a crucial aspect for routine genetic diagnostics as well as for basic research. In this study we present a development and evaluation of comparative-high resolution melting (C-HRM), a new approach for the simultaneous screening of small DNA changes and gene CNVs. In contrast to other methods, relative quantification in C-HRM is based on the results obtained during the melting process and calculations of the melting peak height ratio in the multiplex reaction. Validation of the method was conducted on DNA samples from 50 individuals from Duchenne muscular dystrophy (DMD) families, 50 probands diagnosed with familial adenomatous polyposis and a control group of 36 women and 36 men. The results of analyses conducted on fragments of the DMD and APC genes correspond completely (100 %) with the results of previous studies. C-HRM sensitivity in CNV detection was assessed through the analysis of mixed DNA samples with different proportions of a deletion carrier and wild type control. The results are presented as a linear regression with R2 of 0.9974 and imply the capability of the method to detect mosaics. C-HRM is an attractive and powerful alternative to other methods of point mutations and CNV detection with 100 % accuracy in our studied group.
Collapse
|
5
|
Plawski A, Banasiewicz T, Borun P, Kubaszewski L, Krokowicz P, Skrzypczak-Zielinska M, Lubinski J. Familial adenomatous polyposis of the colon. Hered Cancer Clin Pract 2013; 11:15. [PMID: 24148210 PMCID: PMC3843547 DOI: 10.1186/1897-4287-11-15] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 10/04/2013] [Indexed: 12/31/2022] Open
Abstract
Familial adenomatous polyposis (FAP) is a well-defined autosomal dominant predisposition to the development of polyposis in the colon and rectum at unusually early ages. The first symptoms of FAP are diarrhea and blood in the stool. Weight loss and weaknesses occur after the development of advanced tumour. The incidence of the FAP disorder is one per 10000 newborns. There are high levels of heterogeneity with regard to the number and timing of the occurrence of polyps. The classical form of FAP is characterized by the presence of more than 100 polyps, which appear in the second decade of life. The average time of occurrence of polyps is 15 years. The earliest symptoms of polyposis have been observed in a three-year-old child. The polyps are characterized by large potential for the development towards malignant tumour. Malignancy can occur from late childhood onwards. Attenuated adenomatous polyposis coli is characterized by a more benign course of disease in contrast to classical FAP. The occurrence of FAP is associated with mutations in the APC tumour suppressor gene, which was described in 1991. The APC gene is located on chromosome 5q21 and is involved in cell proliferation control. A recessive form of adenomatous polyposis is caused by mutations in the base excision repair gene - MUTYH gene. The MUTYH gene is involved in repairing DNA lesions as a result of oxidative DNA damage. MUTYH associated polyposis (MAP) is a predisposition to the development of polyps of the colon but the number of polyps is lower in comparison to classical FAP. The high risks of cancer observed in these two diseases make them important medical issues. Molecular studies of colonic polyposis have been performed in Poland for over fifteen years. A DNA Bank for Polish FAP patients was established at the Institute of Human Genetics in Poznan in which DNA samples from 600 FAP families have been collected.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Jan Lubinski
- Pomeranian Medical University, Szczecin, Poland.
| |
Collapse
|
6
|
Krawczuk-Rybak M, Jakubiuk-Tomaszuk A, Skiba E, Plawski A. Hepatoblastoma as a result of APC gene mutation. J Pediatr Gastroenterol Nutr 2012; 55:334-6. [PMID: 21866058 DOI: 10.1097/mpg.0b013e318232d4db] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Affiliation(s)
- Maryna Krawczuk-Rybak
- Department of Pediatric Oncology and Haematology, Medical University of Bialystok, Poland.
| | | | | | | |
Collapse
|
7
|
Intestinal pouch complications in patients who underwent restorative proctocolectomy for ulcerative colitis and familial adenomatous polyposis in 1985-2008. POLISH JOURNAL OF SURGERY 2011; 83:161-70. [PMID: 22166319 DOI: 10.2478/v10035-011-0025-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
UNLABELLED Restorative proctocolectomy is considered a surgical treatment of choice in ulcerative colitis (UC) and familial adenomatous polyposis (FAP).The aim of the study was to evaluate postoperative complications in patients who underwent surgery for familial adenomatous polyposis and ulcerative colitis, on the basis of a retrospective data analysis. MATERIAL AND METHODS Data of 138 patients after restorative proctocolectomy performed between 1985 and 2008 were collected at routine follow-up visits in 2004-2008. We evaluated the presence of pouchitis, the degree of ileal pouch mucosa atrophy, the presence of ileal pouch mucosal metaplasia, the presence of ileal pouch malignancies, the necessity for diverting ileostomy, the necessity for pouch resection, and severe faecal incontinence. RESULTS Complications were observed in 45 (32.4%) patients. Thirty-seven patients developed pouchitis (26.6%). Low-degree dysplasia, severe dysplasia or malignancies were observed in total in 20 patients (14.4%). Six (4.3%) operated patients developed other analysed complications. CONCLUSIONS The most common complications of restorative proctocolectomy were dysplasia and pouchitis. The most common complication in patients operated for UC was pouchitis. The low observed incidence of intestinal pouchitis may be attributed to the implemented prophylaxis of inflammation. Dysplasia was the most common complication in patients undergoing proctocolectomy for FAP. Due to an increased risk of dysplastic lesions as compared with UC patients, careful endoscopic follow-up examinations are obligatory in this patient group. Other analysed complications were uncommon and were mostly a consequence of chronic pouchitis. Clinical symptoms of pouch-related problems were similar in both analysed groups.
Collapse
|
8
|
Stec R, Pławski A, Synowiec A, Mączewski M, Szczylik C. Colorectal cancer in the course of familial adenomatous polyposis syndrome ("de novo" pathogenic mutation of APC gene): case report, review of the literature and genetic commentary. Arch Med Sci 2010; 6:283-7. [PMID: 22371760 PMCID: PMC3281354 DOI: 10.5114/aoms.2010.13911] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 08/01/2008] [Accepted: 08/26/2008] [Indexed: 11/17/2022] Open
Abstract
Colorectal cancer (CRC) is one of the most common malignant tumours in Poland. Annually approximately 11 000 new cases of CRC are diagnosed, while the number of deaths caused by CRC approaches 8 000. Five-year survival does not exceed 20%. Familial adenomatous polyposis (FAP) is responsible for about 1% of new cases of CRC. The risk of CRC in FAP syndrome is 100%, and the average age of CRC development is 39 years. Early colectomy is the most effective method of CRC prevention. We report an atypical case of CRC in a patient with FAP caused by 2797-2800delAACA mutation of the APC gene.
Collapse
Affiliation(s)
- Rafał Stec
- Department of Oncology, Military Institute of Medicine, Warsaw, Poland
| | | | | | | | | |
Collapse
|
9
|
Plawski A, Slomski R. APC gene mutations causing familial adenomatous polyposis in Polish patients. J Appl Genet 2009; 49:407-14. [PMID: 19029688 DOI: 10.1007/bf03195640] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Familial adenomatous polyposis (FAP) is a well-known hereditary condition characterised by alimentary system tumours. Tens to thousands of polyps occur in the colon and rectum of the patients. There is a high heterogeneity with regard to the number and time of the occurrence of polyps. The occurrence of FAP is associated with mutations in the APC tumour suppressor gene, which was described in 1991. Since then, many studies have been done to analyse the distribution of mutations in individual populations and to determine the function of the gene and a diagnostic approach to FAP. Here the APC gene was studied with respect to the occurrence of small mutations and large rearrangements in 300 unrelated Polish FAP families. Ninety-seven mutations were identified in 164 families. Out of these mutations, 80 were small mutations, including 58 small mutations that were first identified in the Polish population (42 novel and 16 described previously). An increased frequency of mutation c.3927_3931delAAAGA was observed in 10% of the Polish group. Seventeen large rearrangements were found in 29 families. Out of those rearrangements, 8 repeat rearrangements occurred in 20 families. A problem in fast molecular diagnostics of FAP is a high heterogeneity of mutations in the APC gene. It seems that a multiplex ligation-dependent probe amplification test and searching for small mutations by the use of screening methods at the 5' end of exon 15 and exons 14, 9, 11, 13, 5, and 3, help to improve the molecular diagnostics of FAP in Polish patients.
Collapse
Affiliation(s)
- Andrzej Plawski
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
| | | |
Collapse
|
10
|
DNA Bank for Polish Patients with a Predisposition for Intestinal Polyposis. POLISH JOURNAL OF SURGERY 2009. [DOI: 10.2478/v10035-009-0076-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
11
|
Toma M, Cimponeriu D, Pompilia A, Stavarachi M, Beluşică L, Radu I, Gavrilă L. Molecular analysis of mutations for the adenomatous polyposis coli (APC) gene in Romanian patients with colorectal cancer. J Med Life 2008; 1:423-8. [PMID: 20108522 PMCID: PMC5654204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mutations in adenomatous polyposis coli (APC) gene have not been previously characterized among Romanian patients with colorectal cancer (CRC). We initiate this study to detect the mutations in APC gene in blood and tumor samples collected from 16 patients (10 men and 6 women) and blood samples from 21 first and second degree relatives of the patients. For this the presence of mutations in exons 6, 7, 12, 13, 14 as well as in regions B, L and W of exon 15 was investigated using PCR multiplex. In the same time, we have searched for 5 bp deletions at codon 1061 of APC gene by PAGE and SSCP methods. These methods allowed us to evidence identification of the presence of mutations in samples from 7 individuals. In one patient, was detected a deletion of exon 13th of APC gene both in DNA extracted from blood and tumor samples. Multiple deletions (e.g. in exon 6, 12, and in 15L and 15W regions) in DNA extracted from the tumor sample were detected, but not in DNA probe obtained from blood cells. We can speculate that these mutations are an example of genomic instability accompanying the malignancy. Till now, no mutation affecting 1061 codon of APC gene was identified in the patients investigated in our study.
Collapse
Affiliation(s)
- M Toma
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| | - D Cimponeriu
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| | - A Pompilia
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| | - M Stavarachi
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| | - L Beluşică
- Spitalul Clinic I. Cantacuzino, Bucureşti
| | - I Radu
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| | - L Gavrilă
- Departamentul de Genetică Umană, Institutul de Genetică, Universitatea din Bucureşti;
| |
Collapse
|
12
|
Pławski A, Podralska M, Słomski R. Recurrent APC gene mutations in Polish FAP families. Hered Cancer Clin Pract 2007; 5:195-8. [PMID: 19725996 PMCID: PMC2736979 DOI: 10.1186/1897-4287-5-4-195] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 09/22/2007] [Indexed: 12/02/2022] Open
Abstract
The molecular diagnostics of genetically conditioned disorders is based on the identification of the mutations in the predisposing genes. Hereditary cancer disorders of the gastrointestinal tracts are caused by mutations of the tumour suppressor genes or the DNA repair genes. Occurrence of recurrent mutation allows improvement of molecular diagnostics. The mutation spectrum in the genes causing hereditary forms of colorectal cancers in the Polish population was previously described. In the present work an estimation of the frequency of the recurrent mutations of the APC gene was performed. Eight types of mutations occurred in 19.4% of our FAP families and these constitute 43% of all Polish diagnosed families.
Collapse
Affiliation(s)
- Andrzej Pławski
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | | | | |
Collapse
|
13
|
Attard TM, Giglio P, Koppula S, Snyder C, Lynch HT. Brain tumors in individuals with familial adenomatous polyposis: a cancer registry experience and pooled case report analysis. Cancer 2007; 109:761-6. [PMID: 17238184 DOI: 10.1002/cncr.22475] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Most individuals with Familial Adenomatous Polyposis (FAP) harbor mutations in the APC gene on chromosome 5q21. They are at an increased risk of brain tumors, including cerebellar medulloblastoma, when compared with the general population (Brain Tumor Polyposis-BTP Type 2). Genotype-phenotype correlations between APC gene mutations and central nervous system (CNS) tumors have, thus far not been successful. Herein the authors have pooled their registry experience in BTP type 2 with the published reports. METHODS The authors analyzed their established hereditary CRC Registry for brain tumors in FAP pedigrees (56 families, 213 individuals), pooled their patients with BTP and known APC mutations with those reported thus far elsewhere, and compared the resulting mutation distribution of FAP-BTP with the mutation distribution for APC mutations in the US. RESULTS Twenty-eight patients from 24 families were accrued, the most common brain tumor in BTP was medulloblastoma (60%) predominantly in females (12:5) under the age of 20 (mean age 14.7 SD 9.2). Other histologic subtypes included astrocytoma and ependymoma. Analysis of the pooled APC mutation data by Chi-square test of association shows an odds ratio of 3.7 (P < .005) for all brain tumor subtypes and 13.1 (P < .001) for medulloblastoma in patients harboring segment 2 APC mutation (codons 679-1224) compared to nonsegment 2 mutation. CONCLUSIONS In patients with FAP and identifiable APC gene mutation, CNS tumors, especially medulloblastoma which developed in most cases during childhood, are more common in females with FAP and APC gene mutation in codons 686-1217. Further studies are necessary to determine if this observation and the natural history of medulloblastoma in children justifies novel, aggressive, targeted screening of at-risk individuals.
Collapse
Affiliation(s)
- Thomas M Attard
- Department of Pediatrics, University of Nebraska Medical Center, Creighton University School of Medicine, Omaha, Nebraska 68198, USA.
| | | | | | | | | |
Collapse
|
14
|
Skrzypczak M, Podralska M, Heinritz W, Froster UG, Lipiński D, Słomski R, Pławski A. MYH Gene Status in Polish FAP Patients without APC Gene Mutations. Hered Cancer Clin Pract 2006; 4:43-7. [PMID: 20223003 PMCID: PMC3401920 DOI: 10.1186/1897-4287-4-1-43] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Accepted: 01/10/2006] [Indexed: 01/10/2023] Open
Abstract
Familial Adenomatous Polyposis (FAP) is an inheritable predisposition for the occurrence of numerous polyps in the large intestine. In about 50% of all patients, the occurrence of the disease is conditioned by heterozygotic mutations of the APC gene. Screening for genetic factors in persons without mutations in the APC gene led to the identification of homozygotic mutations of the MYH gene as the cause of the appearance of the polyposis form which is characterized by recessive heritability and a milder course than in the case of the classic form of the disease. The authors examined 90 persons from the DNA bank of patients with FAP from the Institute of Human Genetics of the Polish Academy of Sciences in Poznań in whom no mutations in the APC gene were detected. Two of the most frequent mutations of the MYH gene (Y165C and G382D) were found to be heterozygous in 13% of patients and no other mutations in this gene coding sequence were observed. In the group with heterozygotic occurrence of the mutation in the MYH gene, the disease phenotype was not milder in comparison with the entire examined group and the mean age of the disease manifestation was even lower. This observation allows one to conclude that the employed methods of mutation screening were correct and, in the case of the examined group, the mutation ratio of the MYH gene does not precondition the occurrence of the disease, but it cannot be excluded that it may modify its phenotype. The obtained results indicate that the criteria applied during the process of FAP qualification are more rigorous than those applied in other countries.
Collapse
Affiliation(s)
- Marzena Skrzypczak
- Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland.
| | | | | | | | | | | | | |
Collapse
|
15
|
Muzaffarova TA, Pospekhova NI, Sachkov IY, Kuz'minov AM, Ginter EK, Karpukhin AV. New mutations in the APC gene in familial adenomatous polyposis: detection, characterization, and analysis. Bull Exp Biol Med 2005; 139:352-4. [PMID: 16027851 DOI: 10.1007/s10517-005-0292-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The spectrum of mutations in the APC gene in familial adenomatous polyposis was detected in a sampling from the Russian population. Fifteen new mutations were found. Deletions associated with the loss of only 1 or 2 nucleotides (89% cases) prevailed among new (unique) mutations, while all known deletions were caused by the loss of 4 or 5 nucleotides. The detected differences in the deletion characteristics between unique and repeated mutations in the APC gene were typical of samples of patients from a number of populations. Samplings from different populations were heterogeneous by this sign. The incidence of 1-2-nucleotide deletions among unique and repeated deletions in the APC gene in patient samplings from different countries were in negative correlation.
Collapse
Affiliation(s)
- T A Muzaffarova
- Medical Genetic Research Center, Russian Academy of Medical Sciences, Moscow
| | | | | | | | | | | |
Collapse
|