Reproductive choices and intrafamilial communication in neurogenetic diseases with different self-estimated severities.

BACKGROUND: Low uptake of presymptomatic testing and medically assisted reproduction in families impacted by neurogenetic diseases prompted us to investigate how reproductive options are considered and whether there is a relationship with perceived severity of the disease. We hypothesised that self-estimated severity would influence opinion on reproductive options and that prenatal/preimplantation diagnosis would be a motivation to inform relatives about their risk. METHODS: We invited people impacted by neurogenetic diseases to evaluate the severity of their familial disease using analogic visual scales and to answer questionnaires about reproductive choices and intrafamilial communication. We compared answers between diseases and with the perceived severity of each disease. RESULTS: We analysed 562 questionnaires. Participants were impacted by Huntington disease (n=307), spinocerebellar ataxias (n=114), Steinert myotonic dystrophy (n=82) and amyotrophic lateral sclerosis/frontotemporal dementia (n=59). Self-estimated severity differed between pathologies (p<0.0001). Overall, participants considered prenatal diagnosis (78.0±34.4 out of 100) and preimplantation diagnosis (75.2±36.1 out of 100) justified more than termination of pregnancy (68.6±38.5 out of 100). They were less in favour of gamete donation (48.3±39.8 out of 100) or pregnancy abstention (43.3±40.3 out of 100). The greater the perceived severity of the disease, the more reproductive options were considered justified, except for gamete donation. Prenatal/preimplantation diagnosis was a motivation to inform relatives for only 55.3% of participants (p=0.01). CONCLUSION: Self-estimated severity minimally impacts opinions towards reproductive options. Medically assisted reproduction procedures are rarely sought and do not motivate familial communication.

Who and Why? Requests for Presymptomatic Genetic Testing for Amyotrophic Lateral Sclerosis/Frontotemporal Dementia vs Huntington Disease.

OBJECTIVE: We aimed to describe the population of subjects seeking presymptomatic counseling for amyotrophic lateral sclerosis and/or frontotemporal dementia (ALS/FTD) and compared them with those demanding the well-established presymptomatic test for Huntington disease (HD). METHODS: We retrospectively examined the requests of a cohort of individuals at risk of familial ALS/FTD and 1 at risk of HD over the same time frame of 11 years. The individuals were seen in the referral center of our neurogenetics unit. RESULTS: Of the 106 presymptomatic testing (PT) requests from subjects at risk of ALS/FTD, 65% were seen in the last 3 years. Over two-thirds of the subjects were at risk of carrying mutations responsible for ALS, FTD, or both. Sixty-two percent of the subjects came from families with a known hexanucleotide repeat expansion in C9ORF72. During the same period, we counseled 840 subjects at risk of HD. Subjects at risk of ALS/FTD had the presymptomatic test significantly sooner after being aware of their risk, but were older than those at risk of HD. The youngest subjects requesting the test had the highest disease load in the family (p < 0.05). CONCLUSIONS: Demands for PT for ALS/FTD have been increasingly growing, particularly since the discovery of the C9ORF72 gene. The major specificity of the genetic counseling for these diseases is the unpredictability of the clinical phenotype for most of the genes involved. Awareness of this added uncertainty does not prevent individuals from taking the test, as the dropout rate is not higher than that for HD.

Informing about genetic risk in families with Huntington disease: comparison of attitudes across two decades.

The low uptake of presymptomatic testing in Huntington disease prompted us to question family members on how they handle the transmission of information regarding genetic risk. We hypothesised that in 2019, parents would inform their at-risk children about their genetic risk more and at a younger age than in 2000, given the availability of prenatal diagnosis, French legislation changes since 2011, and recent therapeutic advances. We made a questionnaire available about the transmission of genetic information within families with Huntington disease in 2000 and 2019. We obtained 443 questionnaires (295 in 2019 and 148 in 2000). Participants were mainly at-risk for Huntington disease (n = 113), affected (n = 85), and spouses (n = 154). In 2019, participants had a higher mean education level (p < 0.01) and a mean age of 44.1 ± 15.1 years (vs 48.1 ± 11.4 years in 2000, p < 0.01). They had been informed about the risk of being a carrier at around 30 years of age (29.0 ± 14.2 in 2019 vs 32.2 ± 13.8 in 2000, p = 0.09). However, they would inform at an earlier age (≤18 years, 67% vs 59%, p = 0.16). Information on transmission risk had been given primarily by parents (45% vs 30%, p = 0.06). In addition, genetic testing for relatives unaware of their status was recommended more frequently in 2019 (46% vs 32%, p < 0.001). Respondents in 2019 recommended genetic testing more often but overall attitudes towards information and testing have not changed significantly over the 19-year time period since the questionnaire was first delivered even despite recent clinical trials potential disease modifying therapies.

Reverse pre-symptomatic testing for Huntington disease: double disclosure when 25% at-risk children reveal the genetic status to their parent.

Predictive testing for Huntington disease (HD) in 25% at-risk individuals is testing with full knowledge, and sometimes assuming, that the parent does not want to know his status. The goal of this study was to understand: (1) the differences in the motivation between 25% and 50% at-risk individuals to be tested and (2) the consequences of "double disclosure", including parental reactions. Test requests from 25% at-risk individuals were rare (155/1611, 10%). We compared their motivation with those of 1456 50% at-risk individuals. The principal motivation to have the test for both groups was "to know" (48% versus 58%, p = 0.049), but the desire to have children was more frequent in the 25% at-risk group (32% versus 17%, p < 0.001). Sixty percent of the 25% at-risk group went through the testing procedure: 15% (n = 14) were variant positive for HD. Testees reported four adverse reactions of their parent (22%): one committed suicide and three became depressed. This result highlights the impact of "double disclosure", a bad result for the person themselves and the transmitting parent. It is the responsibility of the team to anticipate this outcome with the 25% at-risk individuals: children revealing the genetic status to their parent. They should help the testees and their family to find a satisfactory solution to help prevent adverse reactions. This includes ensuring that the candidate is well-infomed abour the testing options and consequences to her/himself but also to her/his parent. The at-risk parent should be offered to discuss the implications of their child's testing.

A liminal stage after predictive testing for Huntington disease.

BACKGROUND: Following predictive testing for Huntington disease (HD), knowledge of one's carrier status may have consequences on disease onset. Our study aimed to address two questions. First, does knowledge of being a carrier of the pathological HD mutation trigger onset of the disease? Second, does this knowledge influence self-awareness and allow carriers to identify signs and symptoms of disease onset? METHODS: Between 2012 and 2015, 75 HD mutation carriers were examined using the Unified Huntington's Disease Rating Scale (UHDRS) motor score. Onset estimation made with the disease burden score was compared with UHDRS findings. We collected qualitative data with questionnaires and semistructured interviews. RESULTS: 38 women and 37 men, aged 43.7 years±10.5 (20-68), were interviewed after a mean delay between test and study interview of 10.5 years±4.7 (from 4 to 21 years). Estimation of age at onset was 4.5±8.5 years earlier than data-derived age at onset. Participants were categorised according to their motor score: scores <5 were premanifest (n=35), and scores >5 were manifest carriers (n=40). Self-observation was a major preoccupation for all, independent of their clinical status (82% vs 74%, p=0.57). Among manifest carriers, 56% thought they showed symptoms, but only 33% felt ill. Interestingly, this was also observed in those without motor signs (20% and 9%). Being a mutation carrier did not significantly facilitate recognition of motor signs. Interviews with premanifest carriers allowed the burden of self-observation to be illustrated despite lack of motor signs. CONCLUSIONS: Estimating age at onset based on disease burden score may not be accurate. The transition to disease was experienced as an ambiguous or liminal experience. The view of mutation carriers is not always concordant with medical onset estimation, highlighting the difficulties involved in the concept of onset and its use as an outcome in future disease-modifying trials.

Cognitive profile of patients with glycogen storage disease type III: a clinical description of seven cases.

BACKGROUND: Glycogen storage disease type III (GSDIII) is a rare autosomal recessive disorder due to glycogen debranching enzyme (GDE) deficiency. It results in a multisystemic disease with predominant hepatic and myopathic symptoms. While frequent social maladjustment has been observed in our clinical practice, cognitive and psychological disturbances have never been assessed. The aim of this pilot study was to examine and characterize the cognitive profile of patients with GSDIII. METHODS: Seven patients (six women and one man, mean age: 38.7 ± 11.6 years) with GSDIII underwent a neuropsychological set of tests assessing global cognitive efficiency, executive functions, social cognition, apathy, and episodic memory. RESULTS: All patients presented previous psychopathological history. We observed attention fluctuations for each patient, and impaired global cognitive efficiency with deficiencies in executive functions in 5/7 patients. Emotional skills (social cognition) were impaired in five patients. Memory was mostly preserved. CONCLUSION: The impairment in social cognition (recognition of emotions and ability to attribute mental states to others) and executive functions observed could be a consequence of orbito-frontal dysfunction due to the abnormal glycogen metabolism characteristic of the underlying disease. These results are consistent with the hypothesis of a central nervous system involvement in patients with GSDIII, but need to be confirmed in future research. This could explain the social and economic difficulties, and the lack of compliance to the medical follow-up presented by these patients. It suggests that these disturbances need to be taken into account when planning the medical management of patients with GSDIII.

A phase I trial of adeno-associated virus serotype 1-γ-sarcoglycan gene therapy for limb girdle muscular dystrophy type 2C.

γ-Sarcoglycanopathy or limb girdle muscular dystrophy type 2C is an untreatable disease caused by autosomal recessively inherited mutations of the γ-sarcoglycan gene. Nine non-ambulatory patients (two males, seven females, mean age 27 years; range 16-38 years) with del525T homozygous mutation of the γ-sarcoglycan gene and no γ-sarcoglycan immunostaining on muscle biopsy were divided into three equal groups to receive three escalating doses of an adeno-associated virus serotype 1 vector expressing the human γ-sarcoglycan gene under the control of the desmin promoter, by local injection into the extensor carpi radialis muscle. The first group received a single injection of 3 × 10(9) viral genomes in 100 µl, the second group received a single injection of 1.5 × 10(10) viral genomes in 100 µl, and the third group received three simultaneous 100-µl injections at the same site, delivering a total dose of 4.5 × 10(10) viral genomes. No serious adverse effects occurred during 6 months of follow-up. All nine patients became adeno-associated virus serotype 1 seropositive and one developed a cytotoxic response to the adeno-associated virus serotype 1 capsid. Thirty days later, immunohistochemical analysis of injected-muscle biopsy specimens showed γ-sarcoglycan expression in all three patients who received the highest dose (4.7-10.5% positively stained fibres), while real-time polymerase chain reaction detected γ-sarcoglycan messenger RNA. In one patient, γ-sarcoglycan protein was detected by western blot. For two other patients who received the low and intermediate doses, discrete levels of γ-sarcoglycan expression (<1% positively stained fibres) were also detectable. Expression of γ-sarcoglycan protein can be induced in patients with limb girdle muscular dystrophy type 2C by adeno-associated virus serotype 1 gene transfer, with no serious adverse effects.