Mechanism of intrachromosomal triplications 15q11‐q13: A new clinical report

Vialard, François; Mignon-Ravix, Cécile; Parain, D.; Depétris, D.; Portnoı̈, Marie-France; Moirot, H.; Mattei, Marie-Genevı̀eve

doi:10.1002/ajmg.a.10164

Cited by 30 publications

(44 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are several reports of triplications on chromosomes 2, 5, 7, 9, 10, 13, 15, and 16 [Wang et al, 1999;Reddy and Logan, 2000;Vailard et al, 2003]. To our knowledge, the authors always described an inverted middle repeat, as found in this family.…”

Section: Discussionmentioning

confidence: 56%

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**

Eckel¹,

Wimmer²,

Volleth³

et al. 2006

American J of Med Genetics Pt A

View full text Add to dashboard Cite

Cases of tetrasomy 12p and trisomy 12p are known to be associated with specific phenotypic abnormalities well described in the literature. Here, we report on the unusual case of a partial tetrasomy 12p found in an affected patient and in a mosaic constellation in the patient's mother, who showed no phenotypic abnormality. The index patient was a 16-year-old boy with clinical features similar to the "trisomy 12p syndrome" including mental retardation, macrocephaly, a short nose with anteverted nostrils, and a broad protruding lower lip. G-banding analysis and fluorescence in situ hybridization (FISH) experiments using locus specific YAC DNA probes revealed a derivative chromosome 12 with a partial triplication of the short arm with an inverted copy, flanked by two direct copies. Chromosome analyses in parental lymphocytes showed a chromosomal mosaicism in the phenotypically normal mother, with 12% cells exhibiting the same partial tetrasomy 12p as detected in her son. The allelic pattern of short tandem repeats (STR) in the mother's blood DNA showed that a chimerism can be excluded with high probability. To our knowledge, this is the first report of intrachromosomal triplication on chromosome 12, as well as partial tetrasomy 12p mosaicism. Moreover, as a consequence of the chromosomal aberration in the son it can be concluded that a gonadal mosaicism is present in the mother.

show abstract

Section: Discussionmentioning

confidence: 56%

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**

Eckel¹,

Wimmer²,

Volleth³

et al. 2006

American J of Med Genetics Pt A

View full text Add to dashboard Cite

show abstract

“…In most of the triplications analysed to date, the parental origin has been maternal but this is likely to reflect the high proportion of 15q11 ] q13 triplications among which maternal interchomosomal origin predominates (Wang et al, 1999;Ungaro et al, 2001;Roberts et al, 2002;Vialard et al, 2003). Paternal interchomosomal origin, as in this present case, has been described for triplications of e.g.…”

Section: Parental Origin and Possible Mechanism Of Rearrangementmentioning

confidence: 59%

“…It has been argued that, in the absence of a predisposing rearrangement in a parent, the most likely mechanism by which triplications are generated is a three chromatid event involving one interchromosomal U-type exchange and one intrachromosomal U-type exchange at meiosis 1 (Vialard et al, 2003). This mechanism results in one normal chromosome, one triplicated chromosome and a third dicentric chromosome that would be unstable and eventually lost.…”

Section: Parental Origin and Possible Mechanism Of Rearrangementmentioning

confidence: 99%

See 1 more Smart Citation

A complex medical phenotype in a patient with triplication of 2q12.3 to 2q13 characterized with oligonucleotide array CGH

Mercer

Browne

Barber³

et al. 2009

Cytogenet Genome Res

View full text Add to dashboard Cite

We report an adult female with a left polycystic kidney, patent ductus arteriosus, left streak ovary, bicornuate uterus and deafness who presented with infertility. She has an intrachromosomal triplication of bands 2q12.3 to 2q13, with inversion of the central segment, which arose de novo from a paternal interchomosomal event. The triplication contains 68 known genes within the 7.28 Mb of DNA between base pairs 107,140,721 and 114,416,131. All intrachromosomal triplications are rare and, while partial duplications of 2q have been previously described, this patient is a unique surviving case of a triplication of proximal 2q.

show abstract

“…Alternatively, the triplications could form by U-type exchanges between three chromatids. [26][27][28][29] One exchange between homologous chromatids would take place at the distal breakpoint region, the other at the proximal breakpoint region, between either sister chromatids or homologous chromosomes. Brewer et al 23 proposed a replicationbased mechanism, supported by yeast observations, involving the generation of a dimeric inverted circular intermediate.…”

Section: Discussionmentioning

confidence: 99%

Low-copy repeats at the human VIPR2 gene predispose to recurrent and nonrecurrent rearrangements

2012

View full text Add to dashboard Cite

Submicroscopic structural variations, including deletions, duplications, inversions and more complex rearrangements, are widespread in normal human genomes. Inverted segmental duplications or highly identical low-copy repeat (LCR) sequences can mediate the formation of inversions and more complex structural rearrangements through non-allelic homologous recombination. In a patient with 7q36 inverted duplication/terminal deletion, we demonstrated the central role of a pair of short inverted LCRs in the vasoactive intestinal peptide receptor gene (VIPR2)-LCRs in generating the rearrangement. We also revealed a relatively common VIPR2-LCR-associated inversion polymorphism disrupting the gene in almost 1% of healthy subjects, and a small number of complex duplications/triplications. In genome-wide studies of several thousand patients, a significant association of rare microduplications with variable size, all involving VIPR2, with schizophrenia was recently described, suggesting that altered vasoactive intestinal peptide signaling is likely implicated in the pathogenesis of schizophrenia. Genetic testing for VIPR2-LCR-associated inversions should be performed on available cohorts of psychiatric patients to evaluate their potential pathogenic role.

show abstract

Mechanism of intrachromosomal triplications 15q11‐q13: A new clinical report

Cited by 30 publications

References 14 publications

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**

A complex medical phenotype in a patient with triplication of 2q12.3 to 2q13 characterized with oligonucleotide array CGH

Low-copy repeats at the human VIPR2 gene predispose to recurrent and nonrecurrent rearrangements

Contact Info

Product

Resources

About

Mechanism of intrachromosomal triplications 15q11‐q13: A new clinical report

Cited by 30 publications

References 14 publications

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p,**

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p,**

A complex medical phenotype in a patient with triplication of 2q12.3 to 2q13 characterized with oligonucleotide array CGH

Low-copy repeats at the human VIPR2 gene predispose to recurrent and nonrecurrent rearrangements

Contact Info

Product

Resources

About

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**

Intrachromosomal triplication 12p11.22–p12.3 and gonadal mosaicism of partial tetrasomy 12p^,**