Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7
Complex chromosomal rearrangements are rare events compatible with survival, consisting of an imbalance and/or position effect of one or more genes, that contribute to a range of clinical presentations. The investigation and diagnosis of these cases are often difficult. The interpretation of the pat...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-08-01
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| Series: | Genes |
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| Online Access: | https://www.mdpi.com/2073-4425/14/9/1700 |
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| author | Nicoletta Villa Serena Redaelli Stefania Farina Donatella Conconi Elena Maria Sala Francesca Crosti Silvana Mariani Carla Maria Colombo Leda Dalprà Marialuisa Lavitrano Angela Bentivegna Gaia Roversi |
| author_facet | Nicoletta Villa Serena Redaelli Stefania Farina Donatella Conconi Elena Maria Sala Francesca Crosti Silvana Mariani Carla Maria Colombo Leda Dalprà Marialuisa Lavitrano Angela Bentivegna Gaia Roversi |
| author_sort | Nicoletta Villa |
| collection | DOAJ |
| description | Complex chromosomal rearrangements are rare events compatible with survival, consisting of an imbalance and/or position effect of one or more genes, that contribute to a range of clinical presentations. The investigation and diagnosis of these cases are often difficult. The interpretation of the pattern of pairing and segregation of these chromosomes during meiosis is important for the assessment of the risk and the type of imbalance in the offspring. Here, we investigated two unrelated pediatric carriers of complex rearrangements of chromosome 7. The first case was a 2-year-old girl with a severe phenotype. Conventional cytogenetics evidenced a duplication of part of the short arm of chromosome 7. By array-CGH analysis, we found a complex rearrangement with three discontinuous trisomy regions (7p22.1p21.3, 7p21.3, and 7p21.3p15.3). The second case was a newborn investigated for hypodevelopment and dimorphisms. The karyotype analysis promptly revealed a structurally altered chromosome 7. The array-CGH analysis identified an even more complex rearrangement consisting of a trisomic region at 7q11.23q22 and a tetrasomic region of 4.5 Mb spanning 7q21.3 to q22.1. The mother’s karyotype examination revealed a complex rearrangement of chromosome 7: the 7q11.23q22 region was inserted in the short arm at 7p15.3. Finally, array-CGH analysis showed a trisomic region that corresponds to the tetrasomic region of the son. Our work proved that the integration of several technical solutions is often required to appropriately analyze complex chromosomal rearrangements in order to understand their implications and offer appropriate genetic counseling. |
| first_indexed | 2024-03-10T22:43:02Z |
| format | Article |
| id | doaj.art-14633dab7e63420ca07122d8acce2cb9 |
| institution | Directory Open Access Journal |
| issn | 2073-4425 |
| language | English |
| last_indexed | 2024-03-10T22:43:02Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Genes |
| spelling | doaj.art-14633dab7e63420ca07122d8acce2cb92023-11-19T10:52:28ZengMDPI AGGenes2073-44252023-08-01149170010.3390/genes14091700Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7Nicoletta Villa0Serena Redaelli1Stefania Farina2Donatella Conconi3Elena Maria Sala4Francesca Crosti5Silvana Mariani6Carla Maria Colombo7Leda Dalprà8Marialuisa Lavitrano9Angela Bentivegna10Gaia Roversi11UC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalySchool of Medicine and Surgery, University of Milan-Bicocca, 20900 Monza, ItalyUC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalySchool of Medicine and Surgery, University of Milan-Bicocca, 20900 Monza, ItalyUC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalyUC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalyDepartment of Obstetrics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalyNeonatal Intensive Care Unit, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalyUC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalySchool of Medicine and Surgery, University of Milan-Bicocca, 20900 Monza, ItalySchool of Medicine and Surgery, University of Milan-Bicocca, 20900 Monza, ItalyUC Medical Genetics, Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, ItalyComplex chromosomal rearrangements are rare events compatible with survival, consisting of an imbalance and/or position effect of one or more genes, that contribute to a range of clinical presentations. The investigation and diagnosis of these cases are often difficult. The interpretation of the pattern of pairing and segregation of these chromosomes during meiosis is important for the assessment of the risk and the type of imbalance in the offspring. Here, we investigated two unrelated pediatric carriers of complex rearrangements of chromosome 7. The first case was a 2-year-old girl with a severe phenotype. Conventional cytogenetics evidenced a duplication of part of the short arm of chromosome 7. By array-CGH analysis, we found a complex rearrangement with three discontinuous trisomy regions (7p22.1p21.3, 7p21.3, and 7p21.3p15.3). The second case was a newborn investigated for hypodevelopment and dimorphisms. The karyotype analysis promptly revealed a structurally altered chromosome 7. The array-CGH analysis identified an even more complex rearrangement consisting of a trisomic region at 7q11.23q22 and a tetrasomic region of 4.5 Mb spanning 7q21.3 to q22.1. The mother’s karyotype examination revealed a complex rearrangement of chromosome 7: the 7q11.23q22 region was inserted in the short arm at 7p15.3. Finally, array-CGH analysis showed a trisomic region that corresponds to the tetrasomic region of the son. Our work proved that the integration of several technical solutions is often required to appropriately analyze complex chromosomal rearrangements in order to understand their implications and offer appropriate genetic counseling.https://www.mdpi.com/2073-4425/14/9/1700complex chromosomal rearrangementsarray-CGHgenomic complexitychromosome 7segmental duplications |
| spellingShingle | Nicoletta Villa Serena Redaelli Stefania Farina Donatella Conconi Elena Maria Sala Francesca Crosti Silvana Mariani Carla Maria Colombo Leda Dalprà Marialuisa Lavitrano Angela Bentivegna Gaia Roversi Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 Genes complex chromosomal rearrangements array-CGH genomic complexity chromosome 7 segmental duplications |
| title | Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 |
| title_full | Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 |
| title_fullStr | Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 |
| title_full_unstemmed | Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 |
| title_short | Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7 |
| title_sort | genomic complexity and complex chromosomal rearrangements in genetic diagnosis two illustrative cases on chromosome 7 |
| topic | complex chromosomal rearrangements array-CGH genomic complexity chromosome 7 segmental duplications |
| url | https://www.mdpi.com/2073-4425/14/9/1700 |
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