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GTL banded partial karyotypes showing the normal chromosome 10 and the duplicated chromosome 10 (on the right) from (A) IV.9, (B) IV.5, (C) III.6, (D) III.4, (E) II.2, and (F) III.1.
Contexts in source publication
Context 1
... 3 (III.4, fig 3) was referred for chromosome analysis with the indications of intellectual impairment and short stature at the age of 14 years. On clinical examination at the age of 16, he was borderline microcephalic (head circumference 52.7 cm, 2nd centile). He had deep set eyes, a high nasal bridge with a broad nasal tip, flat midface, large mouth, ...
Context 2
... some studies on the parents of proband 2 had initially been interpreted to show mosaicism for the dup(10)(p14) in the father (III.6). Given the structure of the pedigree, as it sub- sequently came to light, and upon review of the cytogenetic material, his karyotype was reinterpreted as non-mosaic 46,XY,dup(10)(p13p15) ( fig 4C). The duplication of band 10p14 could be observed in chromosomes around the 850 band level. ...
Context 3
... shorter chromosomes at 400-500 band levels, the duplication is observed as a more intense band than the normal 10p14 band present in the homologue, making it diYcult to distinguish the duplication from banding variation. Chromosome studies on the mother of proband 3 also showed dup(10)(p13p15) ( fig 4E). Her daughter had been referred for cytogenetic study in 1987 and a normal karyotype was reported at that time, but upon review of the archived slides her karyotype was reinterpreted as 46,XX,dup(10)(p13p15)mat. ...
Citations
... Voullaire y otros (15) Fechtrup (16) Stone y otros (17) Benzackenet y otros ( ...
... identificadas con estos métodos, es por ello que las técnicas de citogenética molecular, como la hibridización in situ fluorescente, han permitido la identificación precisa del origen de rearreglos cromosómicos complejos, como translocaciones, deleciones y duplicaciones, así como de rearreglos cromosómicos crípticos o cromosomas marcadores.(13,14) Cuando en un cromosoma se detecta material extra, como en este estudio, y no se tiene disponibles las sondas para la región cromosómica afectada que permitirían dar una precisa definición de dicho segmento, se debe apoyar el diagnóstico en las características clínicas del paciente para tratar de identificar la procedencia del segmento adicional (Tabla 1).En los últimos años se han descrito alrededor de 40 casos con trisomía parcial 10p.(15,16,17,19,20) Aún se continúa buscando la correlación con los fenotipos que presentan estos pacientes, a fin de conocer mejor este trastorno infrecuente y poder realizar una terapia adecuada para la mejora de calidad de vida.En este caso en estudio, una de las características a resaltar fue la presencia de agenesia del cuerpo calloso, malformación que puede ocurrir de forma aislada o en asociación con otras alteraciones sistémicas o del sistema nervioso central. ...
Introduction: Duplications are unbalanced structural chromosomal aberrations that affect the genome due to an increase in the gene dosage. According to international literature, chromosome 10 is the most affected by its relationship with intellectual disability and its clinical repercussion. Objective: Describe the correlation between the chromosomal finding and the clinic of the patient with intellectual disability. Case presentation: Case presentation: A cytogenetic study was conducted in the cytogenetics laboratory of the National Center of Medical Genetics, a male patient who was referred for indication that suspected a chromosomal aberration. To perform the karyotype, the technique of lymphocyte culture without exogenous serum and GTG bands was used, according to standardized laboratory techniques. The karyotype revealed an apparent duplication of the short arm of chromosome 10, whose formula is 46, XY, dup (10) (p14p14). Likewise, the karyotype of the parents is normal 46, XX and 46, XY. Conclusions: Most of the clinical characteristics detected in the patient coincide with the 10p partial trisomy, except for the finding of a corpus callosum agenesis. We contributed to the genetic counseling of the family by identifying the etiological nature of the affectation. Keywords: Duplications; chromosome 10; psychomotor retardatio
(PDF) Duplication de novo 10p14 associated with intellectual disability and agenesis of corpus callosum. Available from: https://www.researchgate.net/publication/334895699_Duplication_de_novo_10p14_associated_with_intellectual_disability_and_agenesis_of_corpus_callosum [accessed Sep 26 2019].
... The unbalanced chromosome complement had a high transmission rate in this family, but the small pedigree could be the explanation. Families with unbalanced chromosomal abnormalities segregating in multiple members across generations are few [Aviv et al., 1997; Voullaire et al., 2000]. The duplication 11q14.1 ! ...
Detection of abnormal karyotypes with associated clinical manifestations is an important tool for the identification of genes that confer susceptibility to genetic disorders. We present a family with a duplication 11q14.1-q22.1 resulting from an unbalanced familial insertion, associated with a mild dysmorphic phenotype and mood disorders, mainly major depression. This relatively large duplication of a segment from chromosome 11 is associated with a surprisingly little physical phenotypic effect in this family. The finding of mood disorders in adult members of the family who carry the insertion supports the view that the duplication may be important for the identification of contributing gene(s) to mood disorders. Major depression is considered to be a complex trait with multiple genetic alterations interacting with environmental factors. Array-based comparative genome hybridization (array CGH) analysis with a 1 Mb genomic array, defined the duplication region that extended over 16 Mb from 11q14.1 to 11q22.1. Brain-expressed genes that map within this 16 Mb region, are considered worthy of further investigation as gene(s) contributing to the etiology of major depression.
Familial transmission of chromosome 6 duplications is rare. We report on the first observation of a maternally-inherited pure segmental 6q duplication split into two segments, 6q15q16.3 and 6q16.3q21, and associated with obesity. Obesity has previously been correlated to chromosome 6 q-arm deletion but has not yet been assessed in duplications. The aim of this study was to characterize the structure of these intrachromosomal insertional translocations by classic cytogenetic banding, array-CGH, FISH, M-banding and genotyping using microsatellites and SNP array analysis, in a mother and four offspring. The duplicated 6q segments, 9.75 Mb (dup 1) and 7.05 Mb (dup 2) in size in the mother, were inserted distally into two distinct chromosome 6q regions. They were transmitted to four offspring. A son and a daughter inherited the two unbalanced insertions and displayed, like the mother, an abnormal phenotype with facial dysmorphism, intellectual disability, and morbid obesity. Curiously, two daughters with a normal phenotype inherited only the smaller segment, 6q16.3q21. The abnormal phenotype was associated with the larger proximal 6q15q16.3 duplication. We hypothesize a mechanism for this exceptional phenomenon of recurrent reduction and transmission of the duplication during meiosis in a family. We expect the interpretation of our findings to be useful for genetic counseling and for understanding the mechanisms underlying these large segmental 6q duplications and their evolution. © 2015 Wiley Periodicals, Inc.
© 2015 Wiley Periodicals, Inc.
In total, 200 families were reviewed with directly transmitted, cytogenetically visible unbalanced chromosome abnormalities (UBCAs) or euchromatic variants (EVs). Both the 130 UBCA and 70 EV families were divided into three groups depending on the presence or absence of an abnormal phenotype in parents and offspring.
No detectable phenotypic effect was evident in 23/130 (18%) UBCA families ascertained mostly through prenatal diagnosis (group 1). In 30/130 (23%) families, the affected proband had the same UBCA as other phenotypically normal family members (group 2). In the remaining 77/130 (59%) families, UBCAs had consistently mild consequences (group 3).
In the 70 families with established EVs of 8p23.1, 9p12, 9q12, 15q11.2, and 16p11.2, no phenotypic effect was apparent in 38/70 (54%). The same EV was found in affected probands and phenotypically normal family members in 30/70 families (43%) (group 2), and an EV co-segregated with mild phenotypic anomalies in only 2/70 (3%) families (group 3). Recent evidence indicates that EVs involve copy number variation of common paralogous gene and pseudogene sequences that are polymorphic in the normal population and only become visible at the cytogenetic level when copy number is high.
The average size of the deletions and duplications in all three groups of UBCAs was close to 10 Mb, and these UBCAs and EVs form the “Chromosome Anomaly Collection” at http://www.ngrl.org.uk/Wessex/collection. The continuum of severity associated with UBCAs and the variability of the genome at the sub-cytogenetic level make further close collaboration between medical and laboratory staff essential to distinguish clinically silent variation from pathogenic rearrangement.
