Prenatal diagnosis of chromosome disorders in Tunisian population

Interventions addressing genetic disease burdens within selected countries in the MENA region: a scoping review

BACKGROUND

The MENA region is disproportionately affected by genetic disease. The aim of this research is to scope the region for evidence of genetic services and public health interventions to identify geographic gaps, and to provide a descriptive overview of interventions to identify knowledge gaps.

METHODS

This study is conducted as a scoping review and follows the Arksey & O'Malley scoping review framework.

RESULTS

Seventy-six articles spanning 16 MENA nations met inclusion criteria. Studies included interventions in the form of genetic service provision (n=28), as well as comprehensive programs including pilot programs (n=7), community-based genetics programs (n=6) national-level prevention programs (n=18), and national-level mandatory programs (n=17).

CONCLUSIONS

There is an imbalanced response to genetic disease burdens across the MENA region. More research is warranted where interventions are scarce, particularly to inform development of pilot community-based programs. There is also a need for better monitoring and evaluation of existing nation-wide programs.

The Special Features of Prenatal and Preimplantation Genetic Counseling in Arab Countries

Genetic counseling services have only recently been introduced in most Arab countries, and their utilization is increasing. Prenatal genetic counseling is essential, particularly in the Arab context, which is characterized by high rates of consanguinity. Nevertheless, little is known about the decisions faced by parents and the factors underlying the complex decision making that must occur when accessing these services in Arab countries. Herein, we performed a narrative review to discuss the reported experiences of parents accessing genetic counseling in the prenatal setting in the 22 Arab countries. We also highlight the different types of decisions encountered and the factors influencing them. We report that: (i) utilization of genetic counseling services varies across different Arab countries; (ii) many factors affect decision making and service utilization, especially religion; and (iii) parents are faced with an array of decisions in the prenatal setting, partly driven by increased utilization of prenatal diagnosis and preimplantation genetic testing in some countries. Our work is the first to highlight the different factors and decisions influencing genetic counseling in Arab countries. Understanding these factors is essential for improving genetic counseling services in the region and helping counselors facilitate informed decision making.

Supervised classification approach of biometric measures for automatic fetal defect screening in head ultrasound images

This paper presents an advanced approach for foetal brain abnormalities diagnostic by integrating significant biometric features in the identification process. In foetal anomaly diagnosis, manual evaluation of foetal behaviour in ultrasound images is a subjective, slow and error-prone task, especially in the preliminary treatment phases. The effectiveness of this appearance is strictly subject to the attention and the experience of gynaecologists. In this case, automatic methods of image analysis offer the possibility of obtaining a homogeneous, objective and above all fast diagnosis of the foetal head in order to identify pregnancy behaviour. Indeed, we propose a computerised diagnostic method based on morphological characteristics and a supervised classification method to categorise subjects into two groups: normal and affected cases. The presented method is validated on a real integrated microcephaly and dolichocephaly cases. The studied database contains the same gestational age of both normal and abnormal foetuses. The results show that the use of a support vector machine (SVM) classifier is an effective way to enhance recognition and detection for rapid and accurate foetal head diagnostic.

Knowledge, Attitudes, and Practices of Women Toward Prenatal Genetic Testing

Objectives:

We aim to address public knowledge, attitudes, and practices relative to prenatal genetic testing as a starting point for policy development in Jordan.

Study design:

We conducted a cross-sectional prenatal genetic testing knowledge, attitudes, and practices survey with 1111 women recruited at obstetrics and gynecology clinics nationwide. Data were analyzed using a variety of descriptive and inferential statistical tests.

Results:

The overwhelming majority (>94%) of participants considered prenatal genetic testing, particularly non-invasive prenatal genetic screening, procedures to be good, comfortable, and reasonable, even when the non-diagnostic nature of non-invasive prenatal genetic screening was explained. Likewise, 95% encouraged the implementation of non-invasive prenatal genetic screening within the Jordanian health system, but most preferred it to remain optional. However, women in higher-risk age brackets, in consanguineous marriages, and with less education were significantly less interested in learning about non-invasive prenatal genetic screening. Only 60% of women interviewed were satisfied with the services provided by their obstetric/gynecologist. The more satisfied the women were, the more they are likely to adapt non-invasive prenatal genetic screening.

Conclusions:

In sum, although the data support the receptivity of Jordanian women to national implementation of non-invasive prenatal genetic screening, such policies should be accompanied by health education to increase the genetic literacy of the population and to engage high-risk populations. Thus, this offers rare insight into the readiness of 1 particular Arab population to adapt non-invasive prenatal genetic screening technologies.

Genetics and genomic medicine in Tunisia

Genetics and genomic medicine in Tunisia.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: a systematic review

PURPOSE

We performed a systematic review of the ethical, social, and cultural issues associated with delivery of genetic services in low- and middle-income countries (LMICs).

METHODS

We searched 11 databases for studies addressing ethical, social, and/or cultural issues associated with clinical genetic testing and/or counselling performed in LMICs. Narrative synthesis was employed to analyze findings, and resultant themes were mapped onto the social ecological model (PROSPERO #CRD42016042894).

RESULTS

After reviewing 13,308 articles, 192 met inclusion criteria. Nine themes emerged: (1) genetic counseling has a tendency of being directive, (2) genetic services have psychosocial consequences that require improved support, (3) medical genetics training is inadequate, (4) genetic services are difficult to access, (5) social determinants affect uptake and understanding of genetic services, (6) social stigma is often associated with genetic disease, (7) family values are at risk of disruption by genetic services, (8) religious principles pose barriers to acceptability and utilization of genetic services, and (9) cultural beliefs and practices influence uptake of information and understanding of genetic disease.

CONCLUSION

We identified a number of complex and interrelated ethical, cultural, and social issues with implications implications for further development of genetic services in LMICs.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: protocol for a systematic review

BACKGROUND

There has been little focus in the literature on how to build genetic testing and counseling services in low- and middle-income countries in a responsible, ethical, and culturally appropriate manner. It is unclear to what extent this area is being explored and what form further research should take. The proposed knowledge synthesis aims to fill this gap in knowledge and mine the existing data to determine the breadth of work in this area and identify ethical, social, and cultural issues that have emerged.

METHODS/DESIGN

An integrated knowledge translation approach will be undertaken by engaging knowledge users throughout the review to ensure relevance to their practice. Electronic databases encompassing various disciplines, such as healthcare, social sciences, and public health, will be searched. Studies that address clinical genetic testing and/or counseling and ethical, social, and/or cultural issues of these genetic services, and are performed in low- and middle-income countries as defined by World Bank will be considered for inclusion. Two independent reviewers will be involved in a two-stage literature screening process, data extraction, and quality appraisal. Studies included in the review will be analyzed by thematic analysis. A narrative synthesis guided by the social ecological model will be used to summarize findings.

DISCUSSION

This systematic review will provide a foundation of evidence regarding ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries. Using the social ecological model as a conceptual framework will facilitate the understanding of broader influences of the sociocultural context on an individual's experience with clinical genetic testing and counseling, thereby informing interdisciplinary sectors in future recommendations for practice and policy.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016042894.

Primary Prevention of Hemoglobinopathies by Prenatal Diagnosis and Selective Pregnancy Termination in a Muslim Country: Oman

Hemoglobinopathies (HBP) are the most common genetic disorder in Oman and are in need of prevention programs due to the high incidence of β-thalassemia major and sickle cell disease. Prenatal diagnosis (PD) and selective pregnancy termination is shown to be the most effective prevention tool for the control of HBP. However, PD is not available in Oman thus far because abortion is subject to religious, cultural and ethical issues. We have examined the attitude of a number of Omani HBP carrier couples towards prenatal diagnosis and selective abortion. We have interviewed 35 couples at risk visiting the main premarital clinic in Muscat between Jan 2011 and Jan 2012. Couples were interviewed using a pre-structured questionnaire. The majority would have accepted prenatal diagnosis (94%) if the service would be available in the country but pregnancy termination was greatly influenced by religious values.

Controversies and considerations regarding the termination of pregnancy for foetal anomalies in Islam

Background

Approximately one-fourth of all the inhabitants on earth are Muslims. Due to unprecedented migration, physicians are often confronted with cultures other than their own that adhere to different pdigms.

Discussion

In Islam, and most religions, abortion is forbidden. Islam is considerably liberal concerning abortion, which is dependent on (i) the threat of harm to mothers, (ii) the status of the pregnancy before or after ensoulment (on the 120^th day of gestation), and (iii) the presence of foetal anomalies that are incompatible with life. Considerable variation in religious edicts exists, but most Islamic scholars agree that the termination of a pregnancy for foetal anomalies is allowed before ensoulment, after which abortion becomes totally forbidden, even in the presence of foetal abnormalities; the exception being a risk to the mother’s life or confirmed intrauterine death.

Summary

The authors urge Muslim law makers to also consider abortion post ensoulment if it is certain that the malformed foetus will decease soon after birth or will be severely malformed and physically and mentally incapacitated after birth to avoid substantial hardship that may continue for years for mothers and family members. The authors recommend that an institutional committee governed and monitored by a national committee make decisions pertaining to abortion to ensure that ethics are preserved and mistakes are prevented. Anomalous foetuses must be detected at the earliest possible time to enable an appropriate medical intervention prior to the 120^th day.

Epidemiological profile of common haemoglobinopathies in Arab countries

Haemoglobinopathies including the thalassemias and sickle cell disease are known to be prevalent inherited disorders in most Arab countries with varying prevalence rates and molecular characterisation. β-thalassemia is encountered in polymorphic frequencies in almost all Arab countries with carrier rates of 1-11 % and a varying number of mutations. The most widespread mutation in Lebanon, Egypt, Syria, Jordan, Tunisia and Algeria is the IVS-I-110 (G>A). In the Eastern Arabian Peninsula, the Asian Indian mutations (IVS-I-5 (G>C), codons 8/9 (+G) and IVS-I (-25 bp del)) are more common. The α-thalassemias are encountered in the majority of Arab countries in frequencies ranging from 1 to 58 % with the highest frequencies reported from Gulf countries. The (-α(3.7)) mutation is the most frequent followed by the non-deletional α2 polyadenylation signal mutation (AATAAA>AATAAG) and the α2 IVS1 5-bp deletion. The rates of sickle cell trait in Arab countries range from 0.3 to 30 %, with the Benin, the Arab-Indian and the Bantu haplotypes constituting the bulk of the haplotypes, leading to two major phenotypes; a mild one associated with the Arab-Indian and a severe one with the Benin and Bantu haplotypes. Public health approaches targeting prevention of haemoglobinopathies in Arab countries include newborn screening for sickle cell disease, and premarital screening for carriers of β-thalassemia and sickle cell disease. These services are still patchy and inadequate in many Arab countries recommending the upgrade of these services with strengthening of the education and training of health care providers and raising public awareness on the feasibility of prevention and care for haemoglobinopathies.

[Genetic analysis of Turner syndrome: 89 cases in Tunisia]

Turner's syndrome (TS) affects about 1/2500 female infants born alive. The syndrome results from total or partial absence of one of the two X chromosomes normally present in females. We report the results of a retrospective analysis of 89 cases of TS observed during a six-year period (2000-2005). The patients' age ranged from two days to 51 years at the time of this analysis. Most patients were adults (48%). The aim of this study is to ascertain the principal clinical features leading to a request for a karyotype, searching for a possible relationship between chromosomal anomalies and clinical expression of TS. Pediatric patients were referred for statural retardation or dysmorphic features, while reproduction anomalies were the main indication for karyotyping in patients aged over 20 years. Mosaicism was prevalent (47%), whereas the homogeneous karyotype 45,X was found in only 32% of the patients; structural anomalies were found in 21%. Regarding the advanced age of our patients, we established a relationship between chromosome anomalies and the clinical expression of TS, based on an analysis of stature and reproduction disorders. Short stature and primary amenorrhea were correlated with total deletion of one chromosome X or imbalanced gene dosage due to structural X anomalies. Whereas cases of infertility, recurrent miscarriages and secondary amenorrhea were associated with a mosaic karyotype pattern (45,X/46,XX or 45,X/46,XX/47,XXX ...), with a slight mosaicism in most cases. Thus, chromosome investigations should be performed in cases of reproduction failure even for women with normal stature.

Pattern of chromosomal inversions identified by a birth defects registry, Hawaii, 1986-2002

The aim of the investigation was to describe chromosomal inversions identified by a birth defects registry with respect to chromosomes involved, pregnancy outcome, method of diagnosis, inheritance, sex and diagnosis of major structural birth defects. Cases were derived from a population-based birth defects registry in Hawaii and comprised all infants and fetuses with chromosomal deletions delivered during 1986-2002. A total of 68 cases were identified through a statewide birth defects registry in Hawaii during 1986-2002. The chromosomes involved in the greatest proportion of inversions were chromosomes 6 (18%) and 9 (18%). Live births accounted for 62 (91%) of the cases. Diagnosis was made by amniocentesis or chorionic villus sampling in 60 (88%) of the cases. Of the 43 cases with known inheritance, the inversion was inherited in 40 (93%) and de novo in three (7%). Males accounted for 31 (46%) and females for 37 (54%) of the cases. Major structural birth defects were identified in 12 (18%) of the cases. Inversions diagnosed among infants and fetuses in Hawaii do not appear to affect all chromosomes equally. Most detected inversions occurred among live births and were inherited conditions. Infants and fetuses with inversions are not frequently associated with major structural birth defects.

Attitudes of Israeli Muslims at Risk of Genetic Disorders towards Pregnancy Termination

OBJECTIVES

(1) To examine attitudes towards termination of pregnancy (TOP) among high-risk and non-high-risk (for cystic fibrosis) Arab-Muslims, and (2) to examine the effect of an intervention, which among other things related explicitly to TOP.

METHODS

The study comprised three groups: (1) an intervention group at high risk for CF, which received community genetic counseling; (2) a control group at high risk for CF, and (3) a control group from the general population. The latter two groups were exposed to minimal intervention. Attitudes were measured two or three times during a 1-year period (for the control and intervention groups, respectively).

RESULTS

Predictors of an affected fetus being considered a legitimate cause for TOP were religiosity, familiarity with an affected child, and benefits of the test. Predictors of individuals (hypothetically) choosing abortion in the case of an affected fetus were education and age. No change occurred in the attitudes of participants (either experimental or control groups) in the course of 1 year.

CONCLUSIONS

Other possible intervention options are discussed, and specifically, the advantages of using opinion leaders such as clergy and medical staff.

Pregnancy outcome and prenatal diagnosis of sex chromosome abnormalities in Hawaii, 1986-1999

Sex chromosome abnormalities such as Turner syndrome, Klinefelter syndrome, triple X syndrome, and 47,XYY can be prenatally diagnosed and electively terminated. This investigation examined the pattern of pregnancy outcome of prenatally and postnatally diagnosed sex chromosome abnormalities in Hawaii during 1986-1999 and calculated prenatal diagnosis and subsequent elective termination rates for various factors. Data were obtained from a statewide population-based birth defects registry. The study included 205 detected sex chromosome abnormality cases of which 93 (45%) were live births, 18 (9%) late fetal deaths, 37 (18%) early fetal deaths, and 57 (28%) elective terminations. Pregnancy outcome distribution varied by type of sex chromosome abnormality. Prenatal diagnosis was reported for 132 (64%) of the cases, of which 46 (35%) were subsequently electively terminated. Eleven cases were elective terminations where the sex chromosome abnormality was diagnosed after delivery. Elective termination rates subsequent to prenatal diagnosis differed by sex chromosome abnormality, being highest for 45,X (54%), followed by 47,XXY (46%), 47,XYY (29%), and 47,XXX (17%). Although prenatal diagnosis rates increased significantly over the time period (P = 0.006), the subsequent elective termination rate declined slightly, albeit the trend was not statistically significant (P = 0.440). The prenatal diagnosis rate was highest for the 35-39-year maternal age group, although this age group did not have subsequent elective termination rates higher than other maternal age groups. Pregnancy outcome distribution and prenatal diagnosis and subsequent elective termination of sex chromosome abnormalities appeared to depend on the type of sex chromosome abnormality, year of delivery, and maternal age.