AJP Rep 2013; 03(01): 033-036
DOI: 10.1055/s-0032-1331377
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Confined Blood Chimerism in Monochorionic Dizygotic Twins Conceived Spontaneously

Takashi Kanda
1  Department of Pediatrics, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
,
Masanobu Ogawa
2  Department of Obstetrics and Gynecology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
,
Kazuo Sato
1  Department of Pediatrics, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
› Author Affiliations
Further Information

Publication History

03 May 2012

23 September 2012

Publication Date:
02 January 2013 (online)

  

Abstract

Traditionally, monochorionicity has been regarded as synonymous with monozygosity. However, several recent cases of monochorionic dizygotic twins have shown that monochorionic twins can be dizygous. We report a rare case of monochorionic diamnionic, gender-discordant twins who were conceived spontaneously. Initially, a monochorionic placenta was diagnosed by ultrasonography at 8 weeks of gestation and then confirmed by pathology after delivery. The twins had different genders. A comparison of cytogenetic analyses using peripheral blood lymphocytes and skin fibroblasts revealed that chimerism was confined to blood cells. We have experienced two cases of monochorionic dizygotic twins since 2003. These cases suggest that monochorionic dizygotic twins are not as rare as previously thought.