Project description:<p>To define a genetic syndrome of combined immunodeficiency, severe autoimmunity, and developmental delay, 4 patients from two families who had similar syndromic features were studied. To identify disease-causing mutations, we performed whole exome sequencing for one patient and her healthy parent from Family 1 and also for one patient from Family 2. Disease segregated with novel autosomal recessive mutations in a single gene, tripeptidyl-peptidase II (<i>TPP2</i>) gene. The result defines a new human metabolic immunodeficiency.</p>
Project description:Primary autosomal recessive microcepahly and Seckel syndrome spectrum disodrers (MCPH-SCKS) include a heterogenous group of autosomal recessive inherited diseases characterized by primary (congenital) microcephaly, the absence of visceral abnormalities and a variable degree of cognitive impairment, short stature and facial dysmorphism. Recently, biallelic mutations in the nuclear pore complex (NPC) component nucleoporin 85 gene (NUP85) were reported to cause steroid-resistant nephrotic syndrome (SRNS). Here we report that homozygous mutations in NUP85 can also cause MCPH-SCKS without SRNS and thereby expand the phenotypic spectrum of NUP85-linked diseases. Structural analysis predicts the identified NUP85 mutation to have neither an effect on NPC architecture nor on its interaction with other NUPs. We show that mutant NUP85 is, however, associated with a reduced number of NPCs, abnormal mitotic spindle morphology, altered expression levels of protein involved in of cytoskeletal dynamics and decreased cell viability in patient cells. These altered biological processes can explain the disease-causative nature of the mutant NUP85 associated with the human phenotype. Our results also indicates the link of common cellular mechanism involved in the MCPH-SCKS spectrum disorders and NUP85-associated diseases. In addition to the previous studies, our results broadened the phenotype spectrum of NUP85-specific human disease and emphasizes a role of NUP85 in the development of the nervous system.
Project description:<p>We describe four patients from two unrelated families of different ethnicities who had primary immunodeficiency predominantly manifesting as susceptibility to EBV-related diseases. We performed whole exome sequencing (P1 and P2 from family 1) or whole genome sequencing (P4 and both parents from family 2) in those two families and identified homozygous frameshift or in-frame deletions in CD70 in these patients which abolished either CD70 surface expression or binding to its counter structure CD27. Sanger sequencing identified the same homozygous <i>CD70</i> mutation in P3, which is not included in the dbGaP submission. Autosomal recessive CD70 deficiency is a novel cause of combined immunodeficiency and EBV-associated diseases, reminiscent of CD27 deficiency.</p>
Project description:26 limb-girdle muscular dystrophy patients from Latvia and 34 patients from Lithuania with clinical symptoms of limb-girdle muscular dystrophies, along with 204 healthy unrelated controls were genotyped for 96 most frequent known limb-girdle muscular dystrophies causing mutations for the region, using VeraCode GoldenGate system. More information can be found in article Robust genotyping tool for autosomal recessive type of limb-girdle muscular dystrophies in BMC Musculoskeletal Disorders by I. Inashkina et al.