The First Asian, Single-Center Experience of Blastocyst Preimplantation Genetic Diagnosis with HLA Matching in Thailand for the Prevention of Thalassemia and Subsequent Curative Hematopoietic Stem Cell Transplantation of Twelve Affected Siblings

Table 3

PGD results of embryos that underwent screening for thalassemia.

	α-Thalassemia	α-Thalassemia-HLA	β-Thalassemia	β-Thalassemia-HLA	Total
Stimulation cycles	57	2	60	102	221
Oocytes retrieved	791	84	925	1449	3249
Mature (%/oocyte retrieved)	635 (80.3%)	69 (82.1%)	732 (79.1%)	1178 (81.3%)	2614 (80.5%)
2PN (%/mature)	468 (73.7%)	48 (69.6%)	573 (78.3%)	911 (77.3%)	2000 (76.5%)
Additional screening^a
None	38 (66.7%)	2 (100%)	34 (56.7%)	88 (86.3%)	162 (73.3%)
All chromosomes (CGH)	15 (26.3%)	0	23 (38.3%)	14 (13.7%)	52 (23.5%)
Chromosome 21 (PCR)	4 (7.0%)	0	3 (5.0%)	0	7 (3.2%)
Cycles
With embryos for biopsy	51 (89.5%)	2 (100%)	54 (90.0%)	93 (91.2%)	200 (90.5%)
With suitable embryo(s)^b	47	2	52	58	159
With no suitable embryo(s)^b	4	0	2	35	41
With no embryos for biopsy	6 (10.5%)	0	6 (10.0%)	9 (8.8%)	21 (9.5%)
Number of biopsied embryos	259	23	326	572	1180
Embryo screening results^c
Suitable	146 (56.4%)	6 (26.1%)	197 (60.4%)	94 (16.4%)	443 (37.5%)
Chromosome(s) screened	24	0	69	6	99
Chromosome(s) not screened	122	6	128	88	344
Nonsuitable	108 (41.7%)	17 (73.9%)	125 (38.4%)	466 (81.5%)	716 (60.7%)
Thalassemia-affected^d	80	6	79	37	202
Abnormal chromosome(s)	28	3	46	55	132
HLA nonmatch	—	8	—	374	382
No result^e	5 (1.9%)	0	4 (1.2%)	12 (2.1%)	21 (1.8%)

^aChromosome screening additional to thalassemia and (if appropriate) HLA testing scheduled to occur if biopsiable embryos were obtained. ^bSuitable refers to suitability for clinical use (embryo transfer) based upon genetic screening results. ^cFor cases with additional HLA screening or chromosome 21 analysis, testing was performed simultaneously with thalassemia testing. Embryos affected by thalassemia and with abnormal chromosome 21 content were listed as thalassemia-affected. ^dEmbryos affected by thalassemia and were an HLA mismatch were listed as thalassemia-affected. For cases with additional comprehensive chromosome screening, CGH was performed first and only embryos with no detectable abnormalities were subsequently screened for thalassemia (and HLA if required). Embryos with normal chromosome content that were affected by thalassemia and were an HLA mismatch were listed as thalassemia-affected. Thalassemia-affected for α-thalassemia cases are those with embryos with the genetics for HbH disease or α-thalassemia major. Embryos with the genetics for α-thalassemia trait or silent carriers were considered clinically suitable. Thalassemia-affected for β-thalassemia cases are those embryos with the genetics for thalassemia intermedia, thalassemia major, or HbE/β-thalassemia. Embryos which were β-thalassemia carriers were considered suitable for clinical use. Embryos heterozygous or homozygous for the HbE allele were also considered clinically suitable, although the former was preferentially transferred over the latter. ^eThese embryos failed to produce a result from initial biopsy (and if performed, rebiopsy) and were not suitable for further biopsy.