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 , 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 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 Fema