Kym Boycott is a Professor of Pediatrics at the University of Ottawa in Canada, where she is a Clinical Geneticist at the Children’s Hospital of Eastern Ontario (CHEO), Chair of the Department of Genetics, and a Senior Scientist at the CHEO Research Institute. Dr. Boycott is a Tier 1 Canada Research Chair in Rare Disease Precision Health whose research program bridges clinical genomics to basic research and is focused on understanding the molecular pathogenesis of rare diseases to improve patient care and family well-being. She leads the national Care4Rare Canada Consortium integrating genomic and other –omic technologies to improve our understanding of rare disease, with a particular focus on solving the unsolved and most difficult rare diseases. To leverage these discoveries, she co-leads the Canadian Rare Diseases: Models & Mechanisms Network, established to catalyze connections between newly discovered rare disease genes and basic scientists who can rapidly study them in model systems. Globally, she moves the rare disease agenda forward as part of the Global Commission to End the Diagnostic Odyssey for Children.
Outcome of over 1500 matches through the Matchmaker Exchange for rare disease gene discovery: The 2-year experience of Care4Rare Canada
Matchmaking through the MME is an effective way to investigate novel candidate genes; however, it is a labor-intensive process. Engagement from the community to contribute phenotypic, genotypic, and inheritance data will ensure that matchmaking continues to be a useful approach in the future.
PLPHP deficiency: clinical, genetic, biochemical, and mechanistic insights
The vitamin B6-responsive disorders (B6RDs) are a clinically and genetically heterogeneous group of rare, autosomal recessive conditions (Clayton, 2006) with the hallmark feature of seizures uniquely responsive to treatment by the B6 vitamers pyridoxine and/or pyridoxal-5′-phosphate (PLP) (Baumgartner-Sigl et al., 2007; Basura et al., 2009). PLP is a cofactor for over 160 distinct catalytic functions (Percudani and Peracchi, 2009), including enzymes involved in glucose, lipid and amino acid metabolism (John, 1995; Percudani and Peracchi, 2003; Eliot and Kirsch, 2004), and for the synthesis of neurotransmitters, making it an essential vitamer for normal brain function (Surtees et al., 2006).
Addressing Challenges in the Diagnosis and Treatment of Rare Genetic Diseases
Here, we discuss the increasing opportunity for diagnosis and therapy of rare diseases and how to tackle the associated challenges.
Pyridoxine-dependent epilepsy in zebrafish caused by Aldh7a1 deficiency
PYROXIDINE-DEPENDENT epilepsy (PDE, MIM #266100) is a rare autosomal recessively inherited metabolic disease (Gospe 2017) in which intractable and recurrent neonatal or infantile seizures are alleviated uniquely by high doses of pyridoxine (Pyr, vitamin B6) or pyridoxal 5′-phosphate (PLP) (Baxter 2001; Mills et al. 2006; Stockler et al. 2011). When untreated, PDE can lead to death, usually of status epilepticus (Gospe 2017). This condition is caused by mutations in the lysine degradation gene ALDH7A1 (Mills et al. 2006) that encodes α-aminoadipic-semialdehyde-dehydrogenase, which is also known as “Antiquitin” (Lee et al. 1994) due to its remarkable level of conservation through evolution (Supplemental Material, Figure S1). Loss of ALDH7A1 enzyme function leads to the pathogenic accumulation of the lysine intermediates aminoadipate semialdehyde (AASA) and its cyclic equilibrium form piperideine 6-carboxylate (P6C) in tissues including the central nervous system (CNS)  (Figure 1). P6C has been shown to react with and inactivate PLP (the active form of vitamin B6), a cofactor for over 140 enzymes including those involved in neurotransmission (Percudani and Peracchi 2003). It is thus hypothesized that the local or global depletion of PLP results in the Pyr-dependent seizures (Clayton 2006), possibly via disturbance of the PLP-dependent biosynthesis of γ-aminobutyric acid (GABA), the main cerebral inhibitory neurotransmitter. So far, clinical data from cerebrospinal fluid (CSF) measurements of these compounds were inconclusive and the pathophysiology of PDE remains to be fully elucidated.
International Cooperation to Enable the Diagnosis of All Rare Genetic Diseases
Provision of a molecularly confirmed diagnosis in a timely manner for children and adults with rare genetic diseases shortens their "diagnostic odyssey," improves disease management, and fosters genetic counseling with respect to recurrence risks while assuring reproductive choices.