Thesis (Ph.D.)--Montana State University--Bozeman, 2006. / Typescript. Chairperson, Graduate Committee: Tomás̆ Gedeon. Includes bibliographical references (leaves 84-86).

Thesis (Ph. D.) -- California Institute of Technology, 2010. / Title from home page (viewed 06/21/2010). Advisor and committee chair names found in the thesis' metadata record in the digital repository. Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 93-94). Also available in electronic version.

No description available.

Certain non-associative algebras have important applications in theoretical Mendelian Genetics. In this thesis we will give definitions to these algebras and study their properties. Some examples will also be given. / Science, Faculty of / Mathematics, Department of / Graduate

Introduction: Fetal medicine practitioners (FMPs) are responsible for making decisions about the appropriateness of a late termination of pregnancy (LTOP) based on their assessment of the severity of the prenatal diagnosis while also taking into account the practical, legal and ethical aspects. This study aimed to investigate the views and experiences of FMPs involved in LTOP decision-making in the Western Cape and how these views may guide decisions to offer LTOP. Specifically, the research questions guiding this study aimed to investigate FMPs views on the Choice on Termination of Pregnancy Act (CTOPA), No. 92 of 1996, as well as their attitudes towards the provision and ethics of LTOP. Methodology: A total of six semi-structured, individual face-to-face interviews were conducted between February and March 2020 in the privacy of the participant's office. All interviews were audio-recorded and transcribed. Interpretive phenomenological analysis was used as a framework to analyse the data and transcripts were managed using NVivo 12 software. Results and Discussion: Participants believed that the CTOPA is based on the principle of gradualism and that while women have reproductive choice, TOP becomes progressively restricted as gestation advances to protect the fetus. However, they felt that the specified cut-offs in the CTOPA are arbitrary and open to interpretation and believed there is a need for further documentation to guide practitioners as to which conditions should be considered for LTOP. When making a decision to offer LTOP, participants considered various factors including fetal age, whether a feticide was required and the prognosis. Participants considered that conditions which qualified as severe were untreatable and would have a significant, long-term negative impact on the individual's functioning and quality of life. When considering acceptability of LTOP, participants felt that LTOP was justified to prevent suffering for both the future child and for the parents. However, participants did not believe that LTOP was justified to prevent all disability. Lastly, participants valued societal consensus when making morally demanding decisions and believed that decisions around LTOP needed to be made by multidisciplinary teams to ensure objectivity, as well as to share the moral burden.

Mental retardation (MR) is a handicap with severe implications not only for thosethat suffer from this disability, but also for their families, society and the welfaresystems which support them. A large proportion of these individuals are afflictedwith the X-linked form of the condition. To date a total of 87 genes have beenimplicated in the pathogenesis of X-linked mental retardation (XLMR).

Genetic counselling students are encouraged to become involved with support groups for genetic conditions. However, their roles within these groups are not well defined and poorly understood and ethical concerns have been raised regarding the appropriateness of such involvement. A limited number of international studies have examined the role of a genetic counsellor in a support group. These studies report broadly on the matter but lack the personal response that qualitative data produces. South African literature is even more limited and no studies (both locally and internationally) have attempted to describe the role of a genetic counsellor in a support group for Huntington disease. This study examines the role of a genetic counsellor in a Huntington Disease support group, specifically the Huntington’s Association of South Africa (HASA). A qualitative research approach was used to interview 17 people who have been involved with HASA in the past seven years. In-person and telephonic interviews were conducted with five genetic counsellors and one psychologist. Two separate focus groups were conducted with a total of 11 support group members and one genetic counsellor (who was also interviewed in-person). The interviews and focus groups were audio recorded and transcribed by a combination of an online software program named Sonix Transcription and manual transcription by the researcher herself. Thematic analysis was done and the results were grouped according to the following five themes that emerged from the data: 1) Is there a role?, 2) Information provider, 3) Emotional support, 4) Practical helper, and 5) Community member. It was found that there is a role for a genetic counsellor in a HASA support group and that the relationship that is formed though such involvement can be mutually beneficial to both the support group members and the genetic counsellor. The genetic counsellor’s role was found to be wide and included specialist and practical roles, as indicated by above mentioned themes two to five. These findings cannot be extrapolated to apply to all support groups due to the unique characteristics and function of different support groups. This was evident in this case as the two branches in SA (Western Cape and Gauteng) seem to function very differently. The research can, however, be used as guideline for involvement with other support groups. This 9 study’s findings made a unique contribution in that it documented in detail the genetic counsellor’s involvement in support groups. The study found that all the participants agreed that HASA should have access to a genetic counsellor, thus it is recommended that future studies should explore the role of a genetic counsellor in support groups for other genetic conditions, as those groups could also find it beneficial.

Since the introduction of presymptomatic testing for Spinocerebellar Ataxia in South Africa, no research has looked at the impact, perceptions or acceptance of such testing within this diverse population. Despite the relatively high frequencies of late onset autosomal dominant conditions in South Africa, the uptake of presymptomatic testing by those at-risk of inheriting these conditions has been lower than that seen internationally. This research project sought to understand these low levels of utilisation, by exploring the perceptions of those at-risk of inheriting Spinocerebellar Ataxia towards presymptomatic testing. In depth semi-structured interviews were conducted with six individuals at-risk of inheriting Spinocerebellar Ataxia. The interviews were transcribed verbatim and thematically analysed. The four themes that emerged from the data included: 1) Caregiving, 2) Relationships, 3) Being At-Risk and 4) Presymptomatic Testing (PT) Perceptions. These themes explore the significant and long-lasting burdens faced both physically and emotionally by the affected individual as well as their relatives. With no currently available way of preventing or curing the condition, those atrisk described being left with a sense of hopelessness and anxiety about their future. The at-risk individuals' perceptions and fears were often linked to their and their family's experiences of the condition. Additionally, their perceptions of presymptomatic testing, although positive, did not correlate with testing utilisation amongst the participants. As such, the current underutilisation of presymptomatic testing in South Africa was found to be due to the at-risk individuals' fears of the result and its' perceived consequences, rather than a negative perception of presymptomatic testing. This is significant as it indicates that the current lack of uptake of presymptomatic testing is due to external factors unrelated to the test itself. As such, genetic counsellors should focus their efforts on counselling the individual through their fears as opposed to primarily offering presymptomatic testing. Although these findings contribute to our understanding of this previous understudied population, they cannot be extrapolated to apply to the entire South African at-risk population due to the small sample size of the study. This knowledge however, may assist in improving the presymptomatic testing process by providing greater insight into the population's experiences and perspectives. Thus, it is recommended that future studies explore ways that genetic counselling sessions and the presymptomatic testing process could be altered to incorporate this knowledge.

Introduction: Fragile X Syndrome (FXS) is the most common genetic cause of intellectual disability (ID) and Autism Spectrum Disorder (ASD). It is caused by the expansion of CGG (Cytosine, Guanine, Guanine) repeats at the 5' untranslated region (UTR) of the Fragile X Mental Retardation gene 1 (FMR1). This gene codes for the Fragile X Mental retardation protein, which is responsible for healthy brain development. This condition is transmitted through an X-linked dominant pattern and is known to affect approximately 1 in 2500–4000 males and 1 in 7000–8000 females. In 2011, two siblings received a positive diagnosis of FXS at the Child Neurology Unit of the Yaoundé Gynaeco-Obstetric and Paediatric hospital in Cameroon. Informal data from the first consultation with their mother (P0), showed that she related her children's condition to a curse from her maternal grandfather, the village's chief. This prompted us to ask four research questions for this project: What is the transmission pattern for FXS in this family? How do families and communities explain the pattern of FXS and other inherited forms of ID in the village? What is the impact of receiving a genetic diagnosis on individuals, families, and communities? And what are the stigma experiences around FXS in this community? As a first step to gather empirical work, a scoping review of the lived experiences of FXS caretakers was conducted. It was revealed that these experiences could broadly be summarised into four main themes, namely: grief experiences, challenges of living with FXS, coping mechanisms, and the need to plan for the future of children with FXS. From this review, it was noted that healthcare workers had limited knowledge and a lack of expertise regarding FXS, whilst there was an overall lack of African qualitative literature on FXS. This set the precedent for the second and third components of the project. Methodology: An ethnographic approach was used in this study. Snowball sampling was used to recruit 92 participants who were 18 years old and above. A topic guide was used to gather data through 10 focus group discussions and 23 in-depth interviews with NVivo 12 used for data analysis. The questionnaire explored participants' understanding of FXS, their lived experiences, the stigma association with FXS, and the effects of receiving a positive or negative genetic diagnosis. Moreover, cascade counselling and testing for FXS was offered to 46 participants. Data gathered from this component was analysed using Epi-info 7.2. and pedigrees were drawn using Cyrillic 3.0.400. Results & Discussion: Cascade testing included 58% of participants (n = 27/46) that were females. The FXS laboratory diagnosis of females showed 14.81% (n = 4/27) with a full mutation, 37.04% (n = 10) had a premutation and 48.15% (n = 13/27) were normal. On the other hand, 21.05% (n=4/19) males had a full mutation. The analysis of this family's pedigree further revealed that the founder of this family was probably a normal transmitting male carrier. Moreover, people in the community and this family described the causes of FXS or inherited forms of ID in four different explanatory models. The curse model was the primary explanatory model and is based on a curse from the chief who bewitched his daughters and wives because they did not mourn his ID servant. Other explanations were the spiritual model that relates FXS to a punishment from God and the psychosocial model, which attributes FXS to events in the prenatal and perinatal periods. Finally, the genetic model is an emerging explanation resulting from the return of the FXS genetic result. Furthermore, receiving a genetic diagnosis resulted in two main themes which were psychological adaptation and communication of the genetic risk of FXS. Receiving a diagnosis was associated with happiness and relief, while the latter described genetic guilts, survivor guilt, and frustrations associated with a family history of FXS and taking care of developmentally delayed children. Lastly, in this community, we identified public stigma directed towards the royal family and courtesy stigma experienced by the royal family members. Most interviewees believed that people from the royal family should have a unique way of addressing FXS children from the chieftaincy because of their position in society. Due to their social position, the royal family uses their status to negotiate marriages with community members. Conclusion: Early detection of carrier status will increase family planning options through genetic counselling, premarital screening, and prenatal diagnosis. My findings identified specific sociocultural challenges that should be addressed during the development and implementation of genetic counselling services. Returning the result of a genetic test can create feelings of guilt in the patient and their relatives. Over time, these families can develop coping mechanisms that revolve around preparing future generations about the risk of having FXS. Hence, health care workers or people who are comfortable talking about FXS should serve as intermediaries for affected families.