Cloning in reproductive medicine

Application of iPS in assisted reproductive technology: sperm from somatic cells?

Infertility is an emotionally charged problem, and it is a condition of increasing incidence. In addition, in 40% to 60% of all infertile couples, it was the male who had a problem that led to infertility. Among the male fertility problems, non-obstructive azoospermia (NOA) (caused by testis failure or impaired spermatogenesis) is the most prevalent. Despite enormous clinical and experimental efforts, treatment of this disorder--assistant reproduction technique (ART) with donor spermatozoa remains controversial. We present the hypothesis that induced pluripotent stem (iPS) cell derived spermatozoa can be a potential source for male gametes for patients with NOA; we support this with the following three evidence: the first is the generation of viable, live-born, fertile mature organism from iPS cells; the second is the successful induced differentiation of male gametes from pluripotent cells in vitro; and the last is the wide use of intracytoplasmic sperm injection (ICSI) in human assisted reproduction. If the hiPS derived spermatozoa prove practical in the generation offspring with ICSI, this method might be able to grant a new chance for NOA patients to have their genetic children with fewer emotional, ethical and legislative problems. To ensure the safety of the technology itself and the production of healthy offspring, further investigations are needed. We also suggest several laboratory and clinical approaches for testing our hypothesis.

POSSIBLE THERAPY OF MALE INFERTILITY BY REPRODUCTIVE CLONING: ONE CLONED HUMAN 4-CELL EMBRYO

This study was conducted to evaluate the preimplantation embryonic potential of adult somatic cells from an infertile man using an interspecies bioassay for quality control and also to create human embryos via somatic cell nuclear transfer (SCNT). Skin tissue was biopsied from infertile man to obtain fibroblast cells. These cells were fused with both enucleated bovine oocytes obtained commercially and human oocytes obtained from his wife. SCNT-reconstructed oocytes were cultured in-vitro. Interspecies SCNT embryos were prepared for PCR and DNA analysis. From 13 SCNT-reconstructed bovine oocytes, 7 embryos developed (54%). DNA sequencing of these interspecies embryos showed the presence of human genomic DNA specific for the fibroblast cells of the man. From three SCNT-reconstructed human oocytes, one developed to the 4-cell stage and was subsequently transferred into the patient's uterus. Blood ss-hCG levels showed a negative pregnancy result. Human fibroblast cells from an infertile patient can promote embryonic development in interspecies SCNT. This is the first evidence of the creation and transfer of a human cloned embryo for reproductive purposes. Even though no pregnancy was established, human reproduction via SCNT may be possible and applicable in the future for patients with severe male or female infertility that have no other alternative options for procreating their own offspring.

Evaluation of the embryonic preimplantation potential of human adult somatic cells via an embryo interspecies bioassay using bovine oocytes

OBJECTIVE

To examine the embryonic preimplantation potential of human adult somatic cells by creating interspecies embryos via somatic cell nuclear transfer (SCNT) using bovine oocytes.

DESIGN

Prospective study.

SETTING

Research facility of Reprogen.

PATIENT(S)

Infertile couples.

INTERVENTION(S)

Enucleated bovine oocytes were fused via SCNT with either human granulosa (HG) or fibroblast (HF) cells and cultured in vitro. Polymerase chain reaction (PCR) and DNA analysis were performed on the interspecies embryos. Parthenogenetically activated embryos served as controls.

MAIN OUTCOME MEASURE(S)

Embryonic preimplantation development after interspecies SCNT.

RESULT(S)

From enucleated bovine oocytes fused with HG cells (n = 48) and HF cells (n = 75), 15 HG- and 22 HF-derived embryos developed, some of which progressed to blastocysts (31.3% vs. 29.3%, respectively). The PCR and DNA analysis showed that the interspecies embryos contained human genomic DNA specific for the individual DNA profile of the HG or HF donor cells used for SCNT. In addition, both bovine- and human-specific mitochondrial DNA was detectable in the interspecies embryos up to the blastocyst stage. Parthenogenetic development was 46.8% and 64.9% for the HG and HF series, respectively. The SCNT efficiency index, defined as the ratio of SCNT and parthenogenetic success rate, was 66.8% for HG cells and 45.5% for HF cells.

CONCLUSION(S)

This interspecies bioassay can be utilized to determine and assess the embryonic preimplantation potential of different types of human adult somatic cells.

Knowledge and attitudes toward human cloning in Israel

The success of mammal cloning in 1997 has brought the issue of human cloning into public discussion. Human cloning has several aspects and potential applications for use in both reproductive and non-reproductive matters. The aim of this study was to evaluate the knowledge and attitudes toward human cloning in Israel. Data from 120 respondents (68 health professionals and 52 non-health professionals), all Jewish, Hebrew speaking with at least 15 years of education each, were collected using two questionnaires that dealt with knowledge and attitudes toward human cloning. Results showed that although health professionals had significantly more knowledge that non-health professionals, all respondents had poor knowledge about cloning. No difference in attitudes was found between the groups. Most respondents opposed human cloning, but more positive attitudes toward non-reproductive cloning were found. The results are discussed in the context of the deficit model. The findings indicate a need to provide information about human cloning to allow people to form their attitudes based on factual knowledge.

In-vitro developmental potential of individual mouse blastomeres cultured with and without zona pellucida: future implications for human assisted reproduction

This study was designed to compare the developmental potential of individual blastomeres derived from 2-, 4-, 6- and 8-cell mouse embryos cultured with and without zona pellucida (ZP). In the first series, one, three, five and seven blastomeres were biopsied from 2-, 4-, 6- and 8-cell embryos respectively, and inserted individually into empty ZP recipients, leaving the remaining blastomere within its original ZP. In the second series, the same protocol was used except that the biopsied blastomeres were cultured without ZP and compared with the remaining blastomere within its original ZP. For the first series, individual blastomeres derived from 2-, 4-, 6- and 8-cell embryos cultured with ZP showed blastocyst development of 82.4, 68.6, 44.4 and 23.1% respectively, with corresponding hatching rates of 70.6, 60.0, 25.9 and 7.7%. For the second series, individual blastomeres cultured without ZP progressed with blastocyst development of 73.3, 64.5, 35.7 and 22.7% respectively. Blastocyst multiplication was achieved most efficiently when using individual blastomeres from 4- and 6-cell embryos. This is the first report on comparative in-vitro propagation of single blastomeres derived from various cleavage stages in a mammalian species. Blastomere cloning with its multiple applications may be envisaged for human assisted reproductive technologies.

Predicting human cloning acceptability: a national Greek survey on the beliefs of the public

BACKGROUND

In the era of human genome research, there is a large theoretical debate among scientists and authorities on the ethical dimension based on the moral liberty of the individuals and the scientific and economic dimension based on the freedom and the independence of the scientific and technological activities. Meanwhile, the understanding of beliefs on human cloning (HC) and its acceptability are important for the development of evidence-based policy making. However, previous research in the field of public beliefs towards human genetics is limited. Therefore, in the present study, we investigated the role of public beliefs as predictors of the acceptability of the respondents to use HC.

METHODS

Personal interviews were conducted with 1020 men and women of urban areas in Greece. Stratified random sampling was performed to select participants. Several scientists, experts in HC, evaluated the content of the instrument initially developed. The final questionnaire was the result of a pilot study.

RESULTS

The acceptability of HC for the cure of incurable diseases and transplantation need is very high (70.7 and 58.6%, respectively). Public's intention to have recourse to HC because of "bringing" back to life a loved person or because of reproductive disorders was reported by 35 and 32.5%, respectively. With respect to the role of beliefs: increasing scores of reasons of social benefits, moral/religious reasons and legislative reasons increased the public's intention to have recourse to HC; inversely, decreasing scores of reasons of human commodification/exploitation increased public's intention to have recourse to HC. Additionally, low rates of church attendance appeared to be correlated with high reported acceptability of HC.

CONCLUSION

There is great public concern regarding the application of HC, which probably reflects the existing ambivalence over the relationship between technology and society. Scientists and policymakers should take into account these indicators of public disquiet and should manage the public involvement in policy decisions, from which they have so far been excluded.

Identifying the public's knowledge and intention to use human cloning in Greek urban areas

PURPOSE

The understanding of the public's knowledge on human cloning (HC) and its acceptability are considered important for the development of evidence-based policy making. The aim of this research study was to investigate the demographic and socioeconomic variables that affect the public's knowledge and intention to use HC in urban areas of Greece. Additionally, the possible association of religiousness with the knowledge and the intention to use HC were also investigated.

METHODS

Individual interviews were conducted with 1020 men and women of urban areas in Greece. Stratified random sampling was performed to select the respondents. Several scientists, experts in HC, evaluated the content of the instrument initially developed. The final questionnaire was consequently the result of a pilot study.

RESULTS

Almost half of the respondents (51.5%) believed that "HC is a sort of in vitro fertilization" and 42.9% that "it has already been applied to human being." They were not aware that "the cloned fetus grows in the woman's uterus" (41.5%) and that "HC could regenerate human organs" (41.7%). The acceptability of human cloning for the cure of terminal diseases and transplantation need is very high (70.7% and 58.6%, respectively). The public's intention to have recourse to cloning on the grounds of "bringing" back to life a loved person or because of reproductive disorders was reported as desire by 35% and 32.5%, respectively. The occupational category (scientists, self-employed, and artists), the Intention to use HC, and the number of children are highly significant predictors of valid knowledge about HC. Low rates of church attendance appeared to relate with high reported Intention to use HC, and increasing scores of valid knowledge about HC increased the public's Intention to use HC.

CONCLUSIONS

A number of specific demographic and socioeconomic characteristics and high scores of knowledge provide a persuasive justification in demonstrating intention toward HC. The current study suggests that these findings should receive further attention by policymakers and scientists within the Greek context.

Biotechnology in reproductive medicine

In this review I am summarizing the past and current progress in the field of pharmaceutical, diagnostic, therapeutic, and reproductive cloning in mammals. Several human gene products can be pharmaceutically explored in transgenic farm animals and employed for medical applications. Preimplantation genetic diagnosis (PGD) is utilizing modern molecular cloning techniques to detect genetic and chromosomal aberrations in early embryos originating from patients with inborn errors at risk for hereditary diseases or age-related risk for abnormal karyotype. Stem cell engineering from early human embryos is creating new and promising but also controversial applications for therapeutic and regenerative medicine. Potential risk factors for reproductive cloning are presented and discussed in the context of possible developmental malformations, frequently observed after embryo culture and cloning in farm animals. Future extension of biotechnology to human reproductive cloning is currently under worldwide dispute.