Biomaterial Database

Genotype-phenotype correlations in Down syndrome identified by array CGH in 30 cases of partial trisomy and partial monosomy chromosome 21. 2009

Robert Lyle, and Frédérique Béna, and Sarantis Gagos, and Corinne Gehrig, and Gipsy Lopez, and Albert Schinzel, and James Lespinasse, and Armand Bottani, and Sophie Dahoun, and Laurence Taine, and Martine Doco-Fenzy, and Pascale Cornillet-Lefèbvre, and Anna Pelet, and Stanislas Lyonnet, and Annick Toutain, and Laurence Colleaux, and Jürgen Horst, and Ingo Kennerknecht, and Nobuaki Wakamatsu, and Maria Descartes, and Judy C Franklin, and Lina Florentin-Arar, and Sophia Kitsiou, and Emilie Aït Yahya-Graison, and Maher Costantine, and Pierre-Marie Sinet, and Jean M Delabar, and Stylianos E Antonarakis

Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland. Robert.Lyle@medisin.uio.no

Down syndrome (DS) is one of the most frequent congenital birth defects, and the most common genetic cause of mental retardation. In most cases, DS results from the presence of an extra copy of chromosome 21. DS has a complex phenotype, and a major goal of DS research is to identify genotype-phenotype correlations. Cases of partial trisomy 21 and other HSA21 rearrangements associated with DS features could identify genomic regions associated with specific phenotypes. We have developed a BAC array spanning HSA21q and used array comparative genome hybridization (aCGH) to enable high-resolution mapping of pathogenic partial aneuploidies and unbalanced translocations involving HSA21. We report the identification and mapping of 30 pathogenic chromosomal aberrations of HSA21 consisting of 19 partial trisomies and 11 partial monosomies for different segments of HSA21. The breakpoints have been mapped to within approximately 85 kb. The majority of the breakpoints (26 of 30) for the partial aneuploidies map within a 10-Mb region. Our data argue against a single DS critical region. We identify susceptibility regions for 25 phenotypes for DS and 27 regions for monosomy 21. However, most of these regions are still broad, and more cases are needed to narrow down the phenotypic maps to a reasonable number of candidate genomic elements per phenotype.

UI	MeSH Term	Description	Entries
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D002872	Chromosome Deletion	Actual loss of portion of a chromosome.	Monosomy, Partial,Partial Monosomy,Deletion, Chromosome,Deletions, Chromosome,Monosomies, Partial,Partial Monosomies
D002891	Chromosomes, Human, Pair 21	A specific pair of GROUP G CHROMOSOMES of the human chromosome classification.	Chromosome 21
D004314	Down Syndrome	A chromosome disorder associated either with an extra CHROMOSOME 21 or an effective TRISOMY for chromosome 21. Clinical manifestations include HYPOTONIA, short stature, BRACHYCEPHALY, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, single transverse palmar crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)	Mongolism,Trisomy 21,47,XX,+21,47,XY,+21,Down Syndrome, Partial Trisomy 21,Down's Syndrome,Partial Trisomy 21 Down Syndrome,Trisomy 21, Meiotic Nondisjunction,Trisomy 21, Mitotic Nondisjunction,Trisomy G,Downs Syndrome,Syndrome, Down,Syndrome, Down's
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000015	Abnormalities, Multiple	Congenital abnormalities that affect more than one organ or body structure.	Multiple Abnormalities
D014314	Trisomy	The possession of a third chromosome of any one type in an otherwise diploid cell.	Partial Trisomy,Chromosomal Triplication,Chromosomal Triplications,Partial Trisomies,Trisomies,Trisomies, Partial,Trisomy, Partial
D055028	Comparative Genomic Hybridization	A method for comparing two sets of chromosomal DNA by analyzing differences in the copy number and location of specific sequences. It is used to look for large sequence changes such as deletions, duplications, amplifications, or translocations.	Array Comparative Genomic Hybridization,Array-Based Comparative Genomic Hybridization,Comparative Genome Hybridization,Array Based Comparative Genomic Hybridization,Comparative Genome Hybridizations,Comparative Genomic Hybridizations,Genome Hybridization, Comparative,Genome Hybridizations, Comparative,Genomic Hybridization, Comparative,Genomic Hybridizations, Comparative,Hybridization, Comparative Genome,Hybridization, Comparative Genomic,Hybridizations, Comparative Genome,Hybridizations, Comparative Genomic