Birth of a healthy infant following trophectoderm biopsy from blastocysts for PGD of beta-thalassaemia major

PGD is a well accepted reproductive choice for couples at genetic risk and involves the diagnosis and transfer of unaffected IVF embryos. PGD for monogenetic diseases is most commonly accomplished by the biopsy of one or two blastomeres from cleavage stage embryos, followed by PCR-based protocols. However, PCR-based DNA analysis of one or two cells is subject to several problems, including total PCR failure, or failure of one allele to amplify. Trophectoderm biopsy at the blastocyst stage enables the removal of more than two cells for diagnosis while being non-invasive to the inner cell mass which is destined for fetal development. The aim of this study was to develop a safe, reliable technique for the biopsy of trophectoderm cells from human blastocysts. This case report demonstrates that removal of trophectoderm cells prior to blastocyst transfer is compatible with implantation and development to term. Here we report successful PGD for beta-thalassaemia following trophectoderm cell biopsy from blastocysts and the birth of a healthy infant.

[Hemoglobinopathies and patients with foreign names]

BACKGROUND

The diagnosis of haemoglobinopathies is of growing importance in Norway because of increasing immigration from countries where haemoglobinopathies are prevalent conditions. The aim of this study was to investigate the relationship between mean corpuscular volume (MCV) and the various haemoglobinopathies diagnosed in Norway.

MATERIAL AND METHODS

For a period of three years, all samples with MCV lower than 70 fl were also examined for beta-thalassaemia and haemoglobin variants HbS, HbC, HbE and HbD. A total of 263 samples with low MCV were analysed by high-pressure liquid chromatography.

RESULTS AND INTERPRETATION

In 18% of the samples, a variant of haemoglobinopathy was found, mainly beta-thalassemia minor. 119 of the samples were from persons with an ethnic background from a country in which these diseases are common; all observed haemoglobinopathies were found in this group. 35% of persons with low MCV and a mainly African or Asian ethnic origin had a heterozygous haeomglobinopathy. Low MCV in patients with a foreign ethnic origin is a useful first step in the diagnosis of haemoglobinopathies.

Evaluation of the national health policy of thalassaemia screening in the Islamic Republic of Iran

We reviewed the medical and economic burden of thalassaemia major with emphasis on prenatal diagnosis for disease prevention as the most economic health care policy approach. The current programme in the Islamic Republic of Iran screens couples just before marriage, identifies carriers and refers them for genetic counselling. We searched the current literature for a refined model and enquired into compliance issues in interviews with physicians, couples and families with affected children. The programme was unsatisfactory in comparison with comparable programmes in the Mediterranean region. We devised a simple decision tree that incorporates cost-effectiveness and technical, methodological and social issues that affect compliance. While revisions to the policy could improve efficiency, follow-up is needed, especially to provide prenatal diagnosis for carrier couples.

Postmortem molecular diagnosis of sickle beta thalassaemia

This report describes a case in which the diagnosis of sickle cell disease (SCD) was established after death. The diagnosis of sickle cell syndrome was made in a 68 year old black patient who was found to have sickled red blood cells in many organs at necropsy although the disease had not been diagnosed during her lifetime. DNA was isolated from a peripheral blood smear obtained on the day of the patient's death. The beta globin gene was polymerase chain reaction amplified and sequenced, revealing that the patient had S-beta(+) thalassaemia. This study shows that blood smears are a suitable source for retrospective DNA analysis studies. This case illustrates that relatively "mild" forms of SCD can be overlooked, despite symptomatology suggestive of a sickle syndrome, and demonstrates the feasibility of the postmortem molecular diagnosis of haemoglobinopathies in such cases.

Thalassemia and related hemoglobinopathies

Hemoglobinopathies are the most common single gene disorders in man. There are several hundred of these disorders though the thalassemias -- alpha and beta and the sickling disorders make up the vast majority. Recent advances in the understanding of the hemoglobin structure and the genetics of its synthesis has contributed significantly to the understanding of these diseases. Disorders include those with reduced globin synthesis, abnormal globin chains and failure to switch globin chain synthesis at the appropriate age. This review focuses on the clinical features, diagnosis and management strategies of the alpha and beta thalassemias, the sickling disorders and touches on a few rarer hemoglobinopathies. It also emphasizes prevention strategies and chronic transfusion safety in countries like India where there are limited resources.

[Successful preimplantation genetic diagnosis for beta-thalassemia using multiplex nested polymerase chain reaction]

OBJECTIVE

To develop single-cell multiplex nested polymerase chain reaction (PCR) assays for preimplantation genetic diagnosis (PGD) in couples at risk of having child with beta-thalassemia.

METHODS

Primers were designed and synthesized according to the documented mutation sites common among Chinese. Venous blood was collected from 4 pairs of husband and wife, all heterozygotes for beta-thalassemia, and underwent multiple nested PCR. Intraooplasmic sperm injection and mechanical bio psy was used to obtain single blastomere. Multiplex nested PCR was used to detect the CD41-42 mutation and the closely linked polymorphic marker, HumTHO1 gene or CD41-42, CD41-28, IVSII654 mutation and HumTHO1 gene in the single blastomeres from four clinical PGD cycles. The normal embryos with high scores capable of continuing to divide were transplanted into the uteri. The process of gestation was observed.

RESULTS

200 lymphocytes were amplified by nested PCR. The average amplification rate of the most common 16 beta-thalassemia mutations in Chinese population was 91.3% and the average rate of allele drop out for different sites was 17.0% without differences between any 2 sites. During the 4 PGD cycles 33 embryos underwent bioassay with a success rate of 100%. 33 blastomeres were obtained to undergo PCR, of which 30 were successfully amplified with an amplification rate of 90.9%. Explicit diagnosis was obtained in 26 of the 30 embryos: 7 normal homozygotes, 11 heterozygotes, and 8 abnormal or complex heterozygotes. One or more embryos were transferred back into the uteri of the 4 women and clinical pregnancy occurred in one woman. Five weeks after the implantation B-mode ultrasonography showed monocyesis, and in the 17th week of gestational period paracentesis of cord blood showed normal homozygote. At last a normal female infant confirming the PGD result had been born, which was the first reported unaffected pregnancy resulting from PGD using multiplex nested PCR for couples as beta-thalassemia gene carriers. The results of diagnosis for embryo all corresponded to those for blastomere. The average ADO rate of blastomere was 13.3% (4/30).

CONCLUSION

PGD using multiplex nested PCR, as an alternative to prenatal diagnosis, is a reliable and effective way to help couples-carriers of pathogenetic genes to get a healthy baby.

Cost-effectiveness of prenatal screening for thalassaemia in Hong Kong

OBJECTIVES

To determine the cost effectiveness of a universal prenatal screening program for alpha- and beta-thalassaemia.

METHODS

We retrospectively reviewed our program from 1998 to 2002, and calculated the direct and indirect costs of various components.

RESULTS

18,936 women were screened at our prenatal clinic and 153 couples were subsequently referred to our Prenatal Diagnostic Centre for counselling and further investigations. In addition, there were 238 tertiary referrals and 157 self-referrals. After investigations, 84 fetuses were at risk of beta-thalassaemia major/beta-E thalassaemia, 19 of them were affected and 18 were aborted. The total expenditure on our program (HK 10.0 million dollars) would be less than the postnatal service costs (HK 40.4 million dollars) for 18beta-thalassaemia major fetuses if they were born. Of 361 women at risk of carrying a homozygous alpha0-thalassaemia fetus, 311 (86.2%) opted for the indirect approach (using serial ultrasound examinations to exclude Hb Bart's disease), and 76 (24.5%) subsequently underwent an invasive test for a definitive diagnosis. The sensitivity and false positive rate of this indirect approach was 100.0% and 2.9% respectively.

CONCLUSION

It is cost effective to run a universal prenatal screening program in an area where both beta-thalassaemia and alpha-thalassaemia are prevalent. The indirect approach can effectively avoid an invasive test in unaffected pregnancies.

The Effect of Chorionic Villus Sampling on Fetal Heart Rate

OBJECTIVE

Fetal heart rate (FHR) variation during chorionic villus sampling (CVS) is a controversial topic. Limited studies have been published on this subject. Our study intended to evaluate the effects of CVS on the FHR.

METHOD

One hundred and sixty-five patients undergoing first-trimester elective CVS for prenatal diagnosis of beta-thalassemia were entered into a prospective study. M-mode FHR was obtained before and immediately after CVS in the patients. Potentially confounding variables also recorded included: gestational age, number of needle passes and placental location.

RESULTS

FHR values before and after CVS were compared using the paired t test and showed no statistically significant differences by 95% confidence. No differences were found in data analyzing gestational age, number of needle passes or placental location.

CONCLUSION

We were unable to detect any significant change in FHR after performing CVS. It seems that FHR is generally not altered by CVS.

Quality assessment in cytogenetic and molecular genetic testing: the experience of the Italian Project on Standardisation and Quality Assurance

The first Italian national trial of external quality assessment in genetic testing was organised within the framework of the "Italian National Project for Standardisation and Quality Assurance of Genetic Tests". Sixty-eight Public Health Service laboratories volunteered for the trial, which involved molecular genetic tests (cystic fibrosis, beta-thalassaemia, familial adenomatous polyposis coli and fragile-X syndrome) and cytogenetic tests (prenatal and postnatal, the latter included cancer cytogenetics). The response rate was high (88.2%). The level of analytical accuracy was good, i.e., the percentage of laboratories that correctly genotyped all samples was 89.3% for cystic fibrosis, 90.9% for beta-thalassaemia, 100% for familial adenomatous polyposis coli (despite two laboratories did not complete the analysis because the amount of DNA was considered insufficient), and 90.5% for fragile-X syndrome. Written reports differed widely and were judged "inadequate" in over 50% of cases. Most laboratories from the present study already have experience in previous European external quality assessments for at least one genetic test; this can explain the higher analytical accuracy in the Italian external quality assessment with respect to quality control programmes in other countries. Collaborative networks are strongly suggested to improve the quality of the reports.

Erythropoietin use in a pregnant Jehovah's witness with anemia and beta-thalassemia: a case report

BACKGROUND

Anemia in pregnancy is seen often because of iron deficiency and the "physiologic dilution" that occurs in the third trimester. Other causes include genetic conditions, such as sickle cell anemia and thalassemias. In cases not responding to iron therapy, patients occasionally require a blood transfusion to restore adequate circulating red blood cell mass. In patients belonging to the Jehovah's Witness sect, transfusion of blood products is not allowed, and treatment of anemia in pregnancy may require use of erythropoietin.

CASE

A 26-year-old, African American woman belonging to the Jehovah's Witness sect presented with anemia associated with beta-thalassemia. Iron therapy and prenatal vitamins did not correct the anemia, and the patient became symptomatic, with fatigue and shortness of breath when walking. Therapy with synthetic erythropoietin corrected the anemia, and the patient had an otherwise-uncomplicated pregnancy and delivery.

CONCLUSION

Synthetic erythropoietin has been used successfully in patients with renal failure and anemia. In pregnancy associated with renal failure and anemia, synthetic erythropoietin has been shown to be safe except for rare cases of hypertension. We treated anemia caused by beta-thalassemia in pregnancy with synthetic erythropoietin to avoid a transfusion in a Jehovah's Witness.

New Strategies in the Treatment of the Thalassemias

In addition to the severe beta thalassemias, hematologists have begun to recognize the more severe forms of alpha thalassemia, namely hemoglobin (Hb) H disease and Hb H/Hb Constant Spring, as well as the beta compound heterozygote, beta thalassemia/HbE. Clinically, variably severe anemia becomes apparent in the first year accompanied by occasionally massive expansion of erythropoiesis. The most anemic patients require regular red blood cell transfusions to avoid death from cardiac failure. However, the inevitable iron accumulation leads to dysfunction, primarily involving the heart, liver, and endocrine system; thus, regularly transfused patients require iron chelation. A major discovery was that allogeneic bone marrow (stem cell) transplantation in severely affected subjects with both alpha and beta thalassemia could result in cure. Current work deals with specific complications, such as iron overload and endocrine, cardiopulmonary, thrombophilic, and osteopenic problems. The thalassemias are likely to benefit in the future from specific gene therapy. There are also important advances in genetic counseling based on results of early fetal diagnosis.

Prenatal diagnosis in a family at risk for beta-thalassemia and hemophilia A: an uncommon association

beta-Thalassemia (thal) is an autosomal recessive disorder with a prevalence of 2-3% in Indians, while hemophilia A is X-linked with a prevalence of 1 in 5,000-10,000 male births. The chances of both these disorders being present together is extremely rare (1 in 250,000). We report an interesting consanguineous family from Western India with a combination of these two disorders, which was referred to us for prenatal diagnosis.

Attitudes towards carrier testing in minors: a systematic review

The objective of this article is to review the attitudes of the different stakeholders (minors, healthcare professionals, parents and relatives of affected individuals) towards carrier testing in minors. The databases Pubmed, Google Scholar, Psychinfo, Biological Abstracts, Francis, Anthropological Index online, Web of Science, and Sociological Abstracts were searched using key words for the period 1990-2004. Studies were included if they were published in a peer reviewed journal in English and described the attitudes of minors, parents or healthcare professionals towards carrier testing in minors in a family context. The results were presented in a summary form. In total 20 relevant studies were retrieved (2 studies reported the attitudes of two stakeholders). Only one study reported the attitudes of adolescents, two studies reported the attitudes of adults who had undergone carrier testing in childhood. In total six studies have been retrieved discussing the parental attitudes towards carrier testing in their children. Over all studies, most parents showed interest in detecting their children's carrier status and responded they wanted their child tested before the age of majority: some parents even before 12 years. Eight studies were retrieved that reported the attitudes of relatives of affected individuals. Most were in favor of carrier testing before 18 years. The studies retrieved suggest that most parents are interested in the carrier status of their children and want their children to be tested before they reach legal majority (and some even in childhood). This can lead to tensions between parents and healthcare professionals regarding carrier testing in minors. Guidelines of healthcare professionals advise to defer carrier testing on the grounds that children should be able to decide for themselves later in life to request a carrier test or not.

Intensification of Chelating-Therapy in Patients with Thalassemia major

With the introduction of "hypertransfusion" regimens the extent of disease- and therapy-related hemosiderosis has become the survival limiting factor for patients with beta-thalassemia major as iron transferred with transfusions cannot be excreted by physiological means. Subsequent introduction of deferoxamine therapy for iron elimination and prophylaxis of hemosiderosis has improved prognosis and life quality of these patients considerably. We report our experience with seven adolescent patients with beta-thalassemia and ineffective subcutaneous therapy and severe hemosiderosis-related organ complications. For that reason they received i. v. intensified chelate therapy. The patients were given 70 to 120 mg/kg DFO 7 days a week continuously via a Port-a-cath or Hickman central venous line. Under high-dose i. v. DFO therapy, serum ferritin levels significantly decreased in all patients. Target serum ferritin levels of 3 000 ng/ml were reached after 12 to 20 months of treatment. In 3 of the 5 patients that were treated for longer than 43 months serum ferritin levels even dropped below 2 000 ng/ml. Serum ferritin levels also correlated well with SQUID examinations. Therefore, monitoring of serum ferritin may be useful to monitor patient's compliance and control intensified DFO therapy. Continuous administration of the intensified DFO therapy induced normalization of liver function and left ventricular cardiac function in all patients who are still alive. Two patients died due to cardiac decompensation. In five patients 19 episodes of central catheter-related infections were observed (1.5 infections per 1 000 catheter days). No DFO-associated allergic reactions nor irreversible organ dysfunction were observed. Our results indicate that intensified i. v. DFO therapy is an effective and safe method for treatment of severe organ dysfunction in patients with thalassemia major. The most severe problems are catheter-related infections and inconsistent long-term compliance.

Clinical application of multiple displacement amplification in preimplantation genetic diagnosis

Multiple displacement amplification (MDA) is a technique used in the amplification of very small amounts of DNA. MDA is reported to yield large quantities of high-quality DNA. The applicability of MDA to single cells was recently demonstrated as a potential technique for preimplantation genetic diagnosis (PGD). This paper shows the first clinical application of MDA in PGD. Two cycles of PGD were performed in two diseases, resulting in two pregnancies. All the diagnoses given on blastomeres were confirmed on the non-transferred whole embryos. The blastomere diagnosis was coupled with short tandem repeat (STR) analysis (16 loci) in all cycles. Allelic drop-out (ADO) assessment and amplification efficiency were evaluated on 40 single lymphocytes derived from parents of each disease. ADO and amplification failure were 10.3 and 2.2% for beta-thalassaemia and 17.9 and 2.2% for cystic fibrosis respectively. HLA matching for A, B and DR was performed successfully on single cell for the beta-thalassaemia family using similar methods to genomic DNA. The PGD protocol used in all diseases consists of MDA amplification, followed by a standard polymerase chain reaction protocol. Although HLA matching was not applied to embryos, its feasibility was shown on single cell DNA amplified by MDA. Altogether, these data show the simplicity and reliability of performing PGD in combination with HLA matching and STR analysis using MDA.

Evaluation of the Bio-Rad VARIANT™ II HbA 2/HbA 1C Dual Program for measurement of hemoglobin concentrations and detection of variants

In this work data obtained on the VARIANT™ II hemoglobin analyzer using the Dual Kit elution system were compared to those obtained with the β-Thalassemia Short Program. Since many laboratories still use an earlier model of the hemoglobin analyzer, the Variant™ 1, these data were also compared to those obtained with the latter instrument. Our study is divided into two parts. The first is an evaluation of the precision of the VARIANT™ II for determining the levels of hemoglobin (Hb)A

Adult Onset of a Thalassemia Intermedia Genotype in Association with a − α− 3.7Homozygosity. Hb G-Accra [β73(E17)Asp→Asn] in Combination with β- and α-Thalassemia in the Same Family

We present the case of a 39-year-old male of mixed Black and Chinese Surinamese origin referred because of abdominal pain and extreme tiredness. The patient reported that he had received a single blood transfusion in his youth and presented at intake with a severe microcytic hypochromic anemia. A chest X-ray and computer tomography (CT)-scan revealed bilateral mediastinal lymphadenopathy and interstitial infiltrates. Elevated Hb F (80%) and an unbalanced synthesis ratio (beta/alpha = 0.18) were compatible with severe beta-thalassemia (thal) intermedia. DNA analysis revealed a double heterozygoty for the -88 (C-->T) and the IVS-II- 654 (C-->T) mutations in the presence of a homozygosity for the -alpha3.7 deletion. The two daughters of the proband were both heterozygous for the IVS-II-654 (C-->T) mutation and the -alpha3.7 deletion. The youngest daughter also carried the Hb G-Accra [beta73(E17)Asp-->Asn] mutation, inherited from the mother. Hb G-Accra, a mutant of presumed Ghanaian origin, described as non pathological in the carrier, is reported for the first time in combination with a severe fbeta(+)thal. The molecular background, haplotype of the mutations and a new A--> polymorphism at -309, 5' to the G(gamma) romoter, are reported.

Placental umbilical cord blood transfusion in transfusion-dependent beta thalassemic patients: a preliminary communication

The term blood substitute is actually a misnomer because only a part of the total functions of the blood is replaced by any available so-called substitute, i.e., oxygen delivery and volume expansion only. Therefore, a more accurate term should be red cell substitute. Cord blood, because of its rich mix of fetal and adult hemoglobin, high platelet and WBC counts, and a plasma filled with cytokine and growth factors, as well as its hypoantigenic nature and altered metabolic profile, has all the potential of a real and safe alternative to adult blood during emergencies due to any etiology of blood loss and anemia. Our experience of 92 units of cord blood transfusion in patients with beta thalassemia with severe anemia (hemoglobin concentration varying from 3.5 to 5.9 g/dl with mean hemoglobin 4.6 g/dl) proved to be extremely effective in 14 patients as an emergency substitute of adult conc RBC transfusion (male: female ratio 1:1, age varying from 6 months to 38 years). In the present series, the collection of the blood varied from 57 ml-136 ml mean 84 ml +/- 7.2 ml SD, median 87 ml, mean packed cell volume 45 +/- 3.1 SD, mean hemoglobin concentration 16.4 g/dl +/- 1.6 g/dl SD. After collection the blood was immediately preserved in the refrigerator and transfused within 72 hours of collection from the consenting mother undergoing lower uterine cesarean section. We did not encounter a single case of immunological or non immunological reaction. We suggest that the medical fraternity use this precious gift of nature, which is free from infection, hypoantigenic with an altered metabolic profile, filled with growth factor and cytokine filled plasma with potential higher oxygen carrying capacity than for adult blood, as an emergency source of blood for the management of transfusion-dependent beta thalassemics.

Mutations associated with beta-thalassemia intermedia in Kuwait

OBJECTIVE

To identify the beta-globin gene mutations associated with beta-thalassemia (beta-thal) intermedia in Kuwait.

SUBJECTS AND METHODS

Eighteen patients from 13 unrelated families, mean age 12.7 +/- 8.1 years, range 4-31 years, were involved in the study. They did not require regular blood transfusion. Complete blood count and cation exchange high-performance liquid chromatography hemoglobin quantitation were carried out using standard techniques. Beta-thal mutations were identified with a combination of PCR amplification, allele- specific oligonucleotide hybridization or direct DNA sequencing. The patients were also screened for the alpha2-globin gene (-3.7 kb) deletion.

RESULTS

Of the 13 families, 4 were homozygous for the IVS-I-II (G-->A) and 4 for the IVS-I-6 (T-->C) mutations, while 1 each was a compound heterozygote for the following mutation combinations: CD 8 (-AA) and -101 (C-->T); IVS-I-6 (T-->C) and CD 19 (A-->G); IVS-II-1 (G-->A) and -28 (A-->C); IVS-I-110 (G-->A) and deltabeta0 deletion. Therefore, homozygosity for two typically mild mutations (IVS-II-1 and IVS-I-6) accounted for 61% of the genotypes in our patients.

CONCLUSION

Our results indicate that screening should commence with these two common alleles in Kuwaiti patients presenting with beta-thal syndrome. Early identification of intermedia patients will avoid the complications following an unnecessary hypertransfusion program.

[Diagnosis of thalassemia by using genechips]

OBJECTIVE

The new technology of genechip is exerting a significant impact on the identification of thalassemia, and allows to rapidly and efficiently detect a number of molecular disorders. The aim of the present study was to explore the application value of the diagnostic genechip in determining thalassemia.

METHODS

The subjects group consisted of 62 children with alpha thalassemia and 93 children with beta thalassemia (60 with thalassemia trait, 33 with thalassemia major) from Guangdong province were tested from July 2002 to July 2003; 115 were males and 40 were females, the age ranged from 1 day to 11 years. These children had mild, moderate or severe anemia. Laboratory examinations showed microcytosis and hypochromocytosis. DNA was extracted from ACD coagulated blood with Invisorb DNA extraction kit. After preparation, the alpha and beta globin gene organization and structure of sample was analyzed by genechip technology.

RESULTS

(1) Heterozygotes, homozygotes and compound heterozygotes of the three commonest deletional alpha thalassemia (--(SEA), -alpha(3.7), -alpha(4.2)) and two non-deletional alpha thalassemia (HbCS, HbQS) were successfully detected. (2) Eight different mutations were identified in 126 chromosomes among 60 cases with beta thalassemia traits and 33 cases with beta thalassemia major, namely CD41-42, IVS-II-654, TATAbox-28, CD17, CD71-72 (+A), betaE(26) CD27-28 (+C) and CD71-72 (+T), with the frequencies of 33.5%, 23.9%, 15.0%, 15.0%, 4.8%, 2.4%, 2.4% and 1.5% respectively. (3) Eight cases (13.3%) in 60 thalassemia traits, two cases (6%) 33 cases with thalassemia major were detected to be combined with alpha thalassemia mutation.

CONCLUSION

(1) The usage of genechip in identifying thalassemia mutations has the advantages of simplicity, economy and shorter time. This technique does not use radioisotope and could also detect alpha and beta thalassemia mutations simultaneously. (2) The occurrence of alpha and beta thalassemia dual heterozygotes is frequent in Guangdong province and the genechip technology is important in genetic counseling and prenatal diagnosis of thalassemia in this area.

Preimplantation genetic diagnosis for β-thalassaemia: the Sardinian experience

OBJECTIVES

To report the experiences on preimplantation genetic diagnosis (PGD) in couples at risk for beta-thalassaemia in Sardinia.

METHODS

23 couples at risk for beta-thalassaemia were included in the PGD programme with a total of 42 cycles performed. Among these, 11 couples were fertile, while the remaining 12 had associated fertility problems. In vitro Fertilization (IVF), PGD and prenatal genetic molecular confirmation protocols and results are reported.

RESULTS

All the patients followed the protocol of ovarian stimulation, oocyte retrieval, intracytoplasmic sperm injection (ICSI), embryo biopsy and genetic analysis. A total of 272 oocytes were fertilized in the regular way, and embryo biopsy was performed on 202 embryos. Out of these 202 embryos, 192 (95%) were successful. The genetic diagnosis was performed on 150 embryos (78.1%). Ninety-eight were identified as unaffected and 75 were transferred in 31 cycles. In the infertile patient group, two biochemical pregnancies (11.1% per transfer), in the fertile patient group, four clinical pregnancies, two twin and two singleton pregnancies (30.8% per transfer), were obtained. The genetic molecular results were confirmed in all pregnancies by first-trimester chorionic villus sampling (CVS).

CONCLUSION

Our study shows that PGD for beta-thalassaemia is an available procedure for couples who wish to avoid termination of pregnancy, except in cases where the IVF cycle efficiency is very poor.