Mol Syndromol. May;8(3) doi: / Epub Feb Maternal Uniparental Disomy 14 (Temple Syndrome) as a Result of a. La disomía uniparental es una patología en la cual las dos copias de un cromosoma son heredadas de un mismo progenitor, en lugar de que. La disomía uniparental hace referencia a la situación en la que las dos copias de un cromosoma provienen del mismo progenitor, en lugar de que una copia.
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And thus, after many months of cogitation, I came to spend one night, from a saturday to a sunday, to put down a draft of this idea in writing.
The obvious lesson to it was that an intact second maternal 15 could not substitute successfully for the missing paternal one. The only healthy offspring must have resulted from gamete complementation or, more likely, from the very early embryonic loss of parental I now turn to another major player in the field of UPD, brought into action by Rob Nicholls et al, the phenomenon of genomic imprinting.
You see here, at first glance, a non-homologous balanced translocation which, through an adjacent meiotic separation, produces a disomic gamete. This slide shows a source to find more information from a book written witn my friend and Colleague Stylianos Emmanuel Antonarakis which was published in by Liss-Wiley in New York.
Most remarkable, is not it? We all known the prestigious names of the Scientists listed here, wich include two illustrious pionneers of this Country, Marco Fraccaro and Paul Polani.
A detailed cytogenetic and molecular characterization of the unjparental rearrangement is presented. Congenital insensivity to pain, anhydrosis CIPA. UPDs, maternal or paternal, for chromosomes 6, 7, 11 and 15 have occured in a variable proportion of the listed syndromes, while both maternal and paternal UPD 14 each delineated a new syndrome. If UPD must result, of two possible new hits, one will take off the singly inherited number, leaving behind a UPD pair made of one free and one attached acrocentric chromosome.
In this diagram from our book, individual 3 has an allele from each parent, as normal and individuals 4 and 5 have only paternal alleles, two contrasted ones for individual 4i.
This is an ambitious title to deal with. In addition, the boy presented with many phenotypic features associated with upd 14 mat along with hypoesthesia to pain, previously unreported in this disorder, and bilateral cryptorchidism, also rarely described.
It was Rob Nicholls diskmia colleagues’ merit to establish that in the rarer cases of PWS without the tiny deletion, a chromosome pair 15 looked pink, painted exclusively of maternally segregating alleles and markers!! Indian Journal dusomia Human Genetics. Edward Spence, Ronald G. As I just said earlier, the specfic identification, as of of individual chromosomes by fluorochromes pionnered thanks to Caperson, Zech et al.
Chromosome abnormalities Q90—Q99 I have selected these examples because, to me, they illustrate some incredible twists of Nature. Retrieved from ” https: An adjacent segregation uniiparental resulted into a nullisomy 14 in a paternal gamete whose deletion has been apparently patched up by duplication of the maternal 14 into an isochromosome, after fertilization.
This page was last edited on 26 Septemberat Pseudohermaphroditism 5-alpha reductase deficiency. Fielding Hejtmancik, Marilyn S. On the other hand, two thirds of the bearers of homologous centric fusions will display a uniparental pair for the involved number.
Obesity after initial failure to thrive developed, while compulsive eating habits were not present, which was helpful for the clinical differential diagnosis of Prader-Willi syndrome.
Maternal Uniparental Disomy 14 (Temple Syndrome) as a Result of a Robertsonian Translocation.
Uniparenttal, in this instance, although normal looking, the second maternal chromosome 15 was lacking the genetic expression of a proper paternal one. Spence et al, Voss et al.
Once in print and published, the idea slept in the medical literature for some years because, at the time of dixomia publication, the means to trace the parental origin of a chromosome were still limited, awaiting the analyses of DNA polymorphisms as schematically shown here.
Also it is of note that if this duplicated allele was that of a recessive trait, the individual would be affected. Specific fluorescence of R and G uniparenta, in human chromosomes. She, in turn, produces a balanced male offspring born after 5 spontaneous abortions. Early genetic diagnosis permits a specific follow-up of children with upd 14 mat in order to optimize the long-term outcome.
Indeed this very observation was to serve at the introduction of a still poorly understood phenomenon, genomic imprinting. Lactic acidosis trifunctionnal protein deficiency.
And since, as a rule, meiotic mis-segregation must result in as many nullisomie as disomic gametes, it did not seem to me too far-fetched an idea to statistically envisage the following possibility, namely that coincidental fertilization and complementation of a nullisomic gamete by one disomic for a same chromosome might indeed occur, thus occasionally causing a diploid conceptus to derive one pair from only one parent.
Here are briefly reviewed some modes of UPD formation for more commonly affected member chromosomes. Many more are documented in the 5 years from 91 to 95 and still quite a few are observed in the last 7 years till now, to the best of my knowledge.
However, if the UPD-causing event happened during meiosis II, the genotype may include identical copies of the uniparental chromosome isodisomyleading to the manifestation of rare recessive disorders.
Uniparental disomy – Wikipedia
The first clinical case of UPD was reported in and involved a girl with cystic fibrosis and unusually short stature who carried two copies of maternal chromosome 7. Expert Reviews in Molecular Medicine. Thus, in these instances, these rarer cases showed maternal UPD 15, along with the lack of a paternal chromosome With time and patience, it was recognized that the imprinting disruption caused by the possession of uniparentap UPD pair could intervene as a cause of some previously known syndrome as well as a help in delineating some new ones.
The figures on slide 21 lend support to some extrapolation to evaluate the baseline frequency of a few of the viable UPDs involved as a cause disease. Von Eggling et al. As a result, recessive traits can be expressed. Osteogenesis imperfecta COL1A2 mutation.