Newsletter # 255, Mon, May 20, 2019
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spring 2019 AMHE Newsletter may 20 Haitian Medical Association Abroad Association Medicale Haïtienne à l'Étranger Newsletter # 255 AMHE NEWSLETTER Editor in Chief: Maxime J-M Coles, MD Editorial Board: Rony Jean Mary, MD Reynald Altema, MD Technical Adviser: Jacques Arpin Genetic Chimerism (Chimera) In this number - Words of the Editor, Maxime Coles,MD - NOAH NY Medical Mission - La chronique de Rony Jean-Mary,M.D. - LA PROMOTION DU DR. COICOU - La chronique de Reynald Altéma,M.D. - Published on the AMHE Facebook page last two weeks - United States’ Occupation of Haiti, Maxime Coles,MD - And more... - AHDH 2 genetically female. know what sex is the predominant and The congenital Chimerism can be then remove the less dominant organ. “tetragametic” through the fertilization of Evolution in medicine has shown that we two separate ova by two spermatozoids may have “missed the boat” because of with aggregation of both eggs at the stage our incapability to perform any genetic “Blastocyst or “zygote”. In other way, testing. this is the merging of two non-identical It is only when they exhibit abnormalities twins and as such, they can be male or like “male-female’ or “hermaphrodite” or female or have mixed intersex skin pigmentation etc. that they may be characteristics. These chimera organisms examined and diagnosed. A variant of develop organ which may have different Chimerism is more noticeable on the sets of chromosomes like a kidney or a “Calico cat” or “tortoisehell cats” with an liver in the same individual may present extra X Chromosome. One can understand different set of chromosomes. Nowadays, the legal ramifications with the implication this phenomenon which was considered for the family and the criminal law extremely rare, is diagnosed more often. overseeing the DNA testing when it needs “Marmosets” are chimeras sharing DNA to be performed. of their fraternal twins after trading blood Two famous examples of Chimerism were through chorionic fusions (Hematopoietic bought to court after DNA testing and Chimeras). Most Chimeras will not showing apparently in 2002, that the realize the changes except when a children of Lydia Fairchild were not hers. difference in the phenotype is subtle, like Her custody rights were challenged and a hitchhiker’s thumb, eyes of different fraud charges were filed. She was denied colors, different hair growth on the public assistance in Washington State and opposite side of the body. They may have later dismissed when the DNA was distinctive marks visible to the ultraviolet matched in her cervical tissue. Another light and resembling to an arrow pointing case in the New England, involving Karen down called “Blaschko’s lines”. Keagan, suspected of not being the Other signs to identify the Chimeras are biologic mother of her adult son in need two populations of red cells, or zygotes for a kidney transplant was challenged in of opposite sex, or ambiguous genitalia. court. This is the lawyer for the They may have hairy patch skin, hair or prosecution in this second case who was eye pigmentation (Heterochromia). They able to state to the court that Lydia may show the genitals of both sexes if the Fairchild had two set of DNA and one was blastocysts were of different sex or able to match her kid’s DNA. I will leave simply demonstrate a combined the debate to Dr Rony Jean Mary for a “ovotestes” as previously known to be a profound explanation in the cases true case of hermaphroditism. We have involved. seen some cases during our training back Foekje Dillema, a Dutch sprinter was home and these cases have always been expelled in 1950 from the national team an object of curiosity and the approach for refusing a mandatory sex test. Later in has always been to wait at puberty to 1953, tests demonstrated a Y-chromosome 3 in her body cells showing she was 46,XX / 2008, the house of Commons in the 46,XY mosaic Female. Another woman United Kingdom concluded that was described in the British Medical embryos should not be allowed to be Journal as having blood containing two made in laboratories. In 2005, the different blood types. United States voted on a bill “The I tried to define through the best of my Human Chimera Prohibition Act” reading, how Genetic Chimerism is knowing that science reached a point presently seen in the world of Genetic and where human and non-human life can be Dr Rony Jean Mary will explain in more easily created in laboratories, showing details some famous cases. I can’t blatant disrespect to human dignity. It conclude without talking about some was found also that the creation of new restrictions imposed on the laboratories. life brings with it zoonotic diseases The Western Europe and the United States detrimental to Humans. Unfortunately, have strict regulations and code of ethics this bill died in Congress and the issue forbidding experimentations using human has never been re-considered in a cells. Moral and legal issues creating legislation. controversies are raised by humans about concern about the right to create human chimera with respect to human dignity. In Maxime Coles MD References: 1- Norton, Aaron; Ozzie Zehner (2008). “Which Half is Mommy? Tetragametic Chimerism and Trans- Subjectivity”. Women study Quarterly. Fall/Winter (3-4): pp. 106-127. 2- Friedman, Lauren. “The Stranger-Than-Fiction Story of A Woman Who Was Her Own Twin”. August 2014 3- Gengozian, N; Batson, JS; Eide, P; (1964). “Hematologic and Cytogenetic Evidence for Hematopoietic Chimerism in the Marmoset, Tamarinus Nigricollis” Cytogenetics. 10 (6): 384-393 4- Strain, L; John CS Dean; Mark PR Hamilton; David T Bonthron (1998). “A True Hermaphrodite Chimera Resulting from Embryo Amalgamation after in-vitro Fertilization”. The New England Journal of Medicine. 338 (3) pp.166-169. 5- “The twin Inside Me: “Extraordinary People”. TV Show. (March 2006) 6- Zimmer, Carl (2007-3-27). “In The Marmoset Family, Things really Do appear to Be all Relative”. The New-York Times. 2010-4-01. 7- Hooper, Rowan (26 March 2007). “Marmosets may carry their siblings sex cells”. New Scientist. 8- Ballantyne, KN; Kayser, M; Grootegoed, JA (2011) “Sex and Gender Issues in competitive sports Investigation of a historic case leads to a viewpoint”. British Journal of Sport Medicine. 46 (8): 614- 617. 9- Barry, Star” In the chimera episode, the fact that the subject was a chimera first established through a camera flash on the skin illuminating skin abnormalities: Ask a Genetician. Stanford School of Medicine (2011-7-25) 4 Se pourrait –il que l’un de vos parents biologiques, voire les deux, ne soient pas vos vrais parents ou progéniteurs ? Chi-merism ou enfant chimérique : un phénomène a ne pas ignorer Au tout début de notre formation médicale, à jusqu’ici. On la dirait même infaillible tellement travers les rudiments de base de cette science elle a pris de l’ampleur au cours de ces énorme appelée La GENETIQUE, nous avons dernières années. toujours appris que du croisement d’un être Mais comme toute autre chose dans ce male d’avec une être femelle s’était trouvé monde, l’ADN a ses limites. On dirait qu’ à assurée la postérité par un dérivé X mesure que l’on avance dans certains généralement appelé progéniture. En effet, domaines, on soulève d’avantage de questions dès les premiers instants de la naissance d’un qu’on n’en a de réponses ou de solutions à y bébé ou dès ses premiers vagissement dans apporter..Ainsi, en parallèle aux multiples l’existence, la première question à se poser par applications de l’ADN et de tout autre type tout un chacun, sciemment ou d’héritage épi-génétique , surtout en matière inconsciemment, est qui sont ou qui pourraient de consanguinité, existe bien un phénomène être les auteurs biologiques d’une telle œuvre, dont on ne parle pas trop et qui s’appelle le chi en l’occurrence l’enfant. ? Et si le problème de mérisme. la maternité d’un point de vue phénotypique a C’est quoi le Chi mérisme ? L’explication la longtemps été résolu, il n’en était pas toujours plus simple est le fait par certains parents de ainsi de la paternité de l’œuvre. posséder plus d’un matériel génétique dans Les doutes pourraient encore planer aussi leur corps et de pouvoir passer à leurs longtemps que possible sur le vrai père d’un progénitures un ADN autre que celui qu’ils enfant. Cependant, avec la découverte de possèdent pour eux mêmes. Ce phénomène l’ADN(Acide Désoxyribo Nucléique) en 1953 est particulièrement présent chez des jumeaux par James Watson et Francis Crick voila déjà dont l’un aurait été résorbé pendant ou après plusieurs décennies, le problème de la la différenciation cellulaire tout en permettant paternité ne se pose presque plus. Ne au fétus survivant de garder son ADN et son cherchent à confirmer une paternité ces jours – matériel chromosomique..La grossesse dans ci que ceux qui n’en ont pas les moyens , le ce cas continue normalement comme étant désir et les raisons de le faire. L’ADN, pourrait- une grossesse simple alors qu’a ses débuts, on dire, a révolutionné la science en des elle était plutôt gémellaire. La personne nait proportions jusque-là impensables ou alors avec son propre matériel génétique mais insoupçonnables. Cette particule cachée dans conserve dans certains de ses organes tels le le noyau d’une cellule, peut accuser ou foie et le rein, l’ADN de l’embryon innocenter des gens. manquant..d’un autre cote, les yeux,la peau, Elle absout des prisonniers injustement les cheveux peuvent tous avoir des accusés de certains crimes et condamnés a charcteristiqies diverses.