INTRODUCTIONWe report the fi rst successful preimplantation genetic diagnosis (PGD) for Hb Bart's hydrops fetalis in Singapore, involving both fresh and frozen embryo replacement cycles.

CLINICAL PICTURETwo couples who were carriers of the Southeast Asian type double gene deletion (--(SEA) deletion carriers) requested for PGD. Couple A had 2 previous affected pregnancies, while couple B have a child of unknown genotypic status.

TREATMENTOne PGD cycle was performed for each couple. The --(SEA) deletion was detected using a gap-PCR strategy. Couple A had 1 fresh-embryo replacement cycle while couple B underwent 2 frozen-embryo replacement cycles.

OUTCOMECouple A achieved a twin pregnancy. Second trimester complications resulted in premature delivery, where 1 baby girl survived. Couple B achieved a singleton pregnancy resulting in delivery of a healthy baby boy. Genotype analysis of all babies confirmed the PGD results consistent with clinically unaffected status.

CONCLUSIONSWe have successfully performed PGD to avoid Hb Bart's hydrops fetalis syndrome.

Adult ; Embryo Transfer ; Female ; Genetic Carrier Screening ; Genetic Testing ; Hemoglobins, Abnormal ; Humans ; Hydrops Fetalis ; diagnosis ; genetics ; prevention & control ; Male ; Minisatellite Repeats ; genetics ; Ovulation Induction ; methods ; Polymerase Chain Reaction ; Pregnancy ; Pregnancy Complications, Hematologic ; diagnosis ; genetics ; prevention & control ; Preimplantation Diagnosis ; Singapore ; Sperm Injections, Intracytoplasmic ; alpha-Globins ; genetics

INTRODUCTIONWe report on the first successful preimplantation genetic diagnosis (PGD) in Singapore.

CLINICAL PICTUREA couple who are beta-thalassaemia carriers and have an affected daughter requested for PGD.

TREATMENTTwo cycles of PGD were performed on the couple. Beta-thalassaemia mutations were detected using a nested PCR and minisequencing strategy, and unaffected embryos were selected for transfer.

OUTCOMEA singleton pregnancy was achieved in the second PGD cycle, resulting in the birth of a healthy baby boy with carrier genotype.

CONCLUSIONSThis case report documents the first successful PGD in Singapore, involving a couple at-risk of transmitting beta-thalassaemia major.

Adult ; Female ; Fertilization in Vitro ; Humans ; Male ; Pregnancy ; Preimplantation Diagnosis ; Risk Factors ; Singapore ; beta-Thalassemia ; diagnosis ; genetics ; prevention & control

INTRODUCTIONWe aimed to develop and implement a short tandem repeat (STR) polymerase chain reaction alternative to fluorescence in situ hybridisation (FISH) for the preimplantation genetic diagnosis (PGD) of chromosomal translocations.

METHODSSelected informative STRs located on translocated arms of relevant chromosomes were used to discriminate between normal and unbalanced chromosome states in each embryo.

RESULTSPGD cycles were performed on five couples where one spouse carried a balanced translocation. 27 embryos were analysed, of which 12 were normal/balanced, 12 were abnormal/unbalanced and three were indeterminate. Four PGD cycles proceeded to embryo transfer, of which two led to pregnancy. The first pregnancy showed a normal male karyotype, and a healthy baby was delivered at term. A second pregnancy unexpectedly miscarried in the second trimester from unknown causes.

CONCLUSIONSTR analysis is a simple and suitable alternative to FISH for detecting unbalanced chromosomal states in preimplantation embryos.

Female ; Fertilization in Vitro ; Humans ; Male ; Microsatellite Repeats ; genetics ; Polymerase Chain Reaction ; methods ; Polymorphism, Genetic ; genetics ; Pregnancy ; Pregnancy Outcome ; Preimplantation Diagnosis ; methods ; Translocation, Genetic ; genetics