@article {963, title = {Absent B cells, agammaglobulinemia, and hypertrophic cardiomyopathy in folliculin-interacting protein 1 deficiency.}, journal = {Blood}, volume = {137}, year = {2021}, month = {2021 01 28}, pages = {493-499}, abstract = {

Agammaglobulinemia is the most profound primary antibody deficiency that can occur due to an early termination of B-cell development. We here investigated 3 novel patients, including the first known adult, from unrelated families with agammaglobulinemia, recurrent infections, and hypertrophic cardiomyopathy (HCM). Two of them also presented with intermittent or severe chronic neutropenia. We identified homozygous or compound-heterozygous variants in the gene for folliculin interacting protein 1 (FNIP1), leading to loss of the FNIP1 protein. B-cell metabolism, including mitochondrial numbers and activity and phosphatidylinositol 3-kinase/AKT pathway, was impaired. These defects recapitulated the Fnip1-/- animal model. Moreover, we identified either uniparental disomy or copy-number variants (CNVs) in 2 patients, expanding the variant spectrum of this novel inborn error of immunity. The results indicate that FNIP1 deficiency can be caused by complex genetic mechanisms and support the clinical utility of exome sequencing and CNV analysis in patients with broad phenotypes, including agammaglobulinemia and HCM. FNIP1 deficiency is a novel inborn error of immunity characterized by early and severe B-cell development defect, agammaglobulinemia, variable neutropenia, and HCM. Our findings elucidate a functional and relevant role of FNIP1 in B-cell development and metabolism and potentially neutrophil activity.

}, keywords = {Adult, Agammaglobulinemia, Animals, B-Lymphocytes, Cardiomyopathy, Hypertrophic, Carrier Proteins, Child, Child, Preschool, Chromosomes, Human, Pair 5, Codon, Nonsense, Consanguinity, Crohn Disease, Developmental Disabilities, Disease Models, Animal, Disease Susceptibility, DNA Copy Number Variations, Female, Heart Defects, Congenital, Humans, Immunologic Deficiency Syndromes, Infections, Loss of Function Mutation, Lymphopenia, Male, Mice, Neutropenia, Pedigree, Uniparental Disomy, Whole Exome Sequencing}, issn = {1528-0020}, doi = {10.1182/blood.2020006441}, author = {Saettini, Francesco and Poli, Cecilia and Vengoechea, Jaime and Bonanomi, Sonia and Orellana, Julio C and Fazio, Grazia and Rodriguez, Fred H and Noguera, Loreani P and Booth, Claire and Jarur-Chamy, Valentina and Shams, Marissa and Iascone, Maria and Vukic, Maja and Gasperini, Serena and Quadri, Manuel and Barroeta Seijas, Amairelys and Rivers, Elizabeth and Mauri, Mario and Badolato, Raffaele and Cazzaniga, Gianni and Bugarin, Cristina and Gaipa, Giuseppe and Kroes, Wilma G M and Moratto, Daniele and van Oostaijen-Ten Dam, Monique M and Baas, Frank and van der Maarel, Silv{\`e}re and Piazza, Rocco and Coban-Akdemir, Zeynep H and Lupski, James R and Yuan, Bo and Chinn, Ivan K and Daxinger, Lucia and Biondi, Andrea} } @article {52, title = {Association Between Absolute Neutrophil Count and Variation at TCIRG1: The NHLBI Exome Sequencing Project.}, journal = {Genet Epidemiol}, volume = {40}, year = {2016}, month = {2016 09}, pages = {470-4}, abstract = {

Neutrophils are a key component of innate immunity. Individuals with low neutrophil count are susceptible to frequent infections. Linkage and association between congenital neutropenia and a single rare missense variant in TCIRG1 have been reported in a single family. Here, we report on nine rare missense variants at evolutionarily conserved sites in TCIRG1 that are associated with lower absolute neutrophil count (ANC; p = 0.005) in 1,058 participants from three cohorts: Atherosclerosis Risk in Communities (ARIC), Coronary Artery Risk Development in Young Adults (CARDIA), and Jackson Heart Study (JHS) of the NHLBI Grand Opportunity Exome Sequencing Project (GO ESP). These results validate the effects of TCIRG1 coding variation on ANC and suggest that this gene may be associated with a spectrum of mild to severe effects on ANC.

}, keywords = {Adult, Aged, Aged, 80 and over, Alleles, Cohort Studies, Female, Gene Frequency, Genotype, High-Throughput Nucleotide Sequencing, Humans, Leukocyte Count, Male, Middle Aged, Mutation, Missense, National Heart, Lung, and Blood Institute (U.S.), Neutropenia, Neutrophils, Sequence Analysis, DNA, United States, Vacuolar Proton-Translocating ATPases}, issn = {1098-2272}, doi = {10.1002/gepi.21976}, author = {Rosenthal, Elisabeth A and Makaryan, Vahagn and Burt, Amber A and Crosslin, David R and Kim, Daniel Seung and Smith, Joshua D and Nickerson, Deborah A and Reiner, Alex P and Rich, Stephen S and Jackson, Rebecca D and Ganesh, Santhi K and Polfus, Linda M and Qi, Lihong and Dale, David C and Jarvik, Gail P} } @article {254, title = {TCIRG1-associated congenital neutropenia.}, journal = {Hum Mutat}, volume = {35}, year = {2014}, month = {2014 Jul}, pages = {824-7}, abstract = {

Severe congenital neutropenia (SCN) is a rare hematopoietic disorder, with estimated incidence of 1 in 200,000 individuals of European descent, many cases of which are inherited in an autosomal dominant pattern. Despite the fact that several causal genes have been identified, the genetic basis for >30\% of cases remains unknown. We report a five-generation family segregating a novel single nucleotide variant (SNV) in TCIRG1. There is perfect cosegregation of the SNV with congenital neutropenia in this family; all 11 affected, but none of the unaffected, individuals carry this novel SNV. Western blot analysis show reduced levels of TCIRG1 protein in affected individuals, compared to healthy controls. Two unrelated patients with SCN, identified by independent investigators, are heterozygous for different, rare, highly conserved, coding variants in TCIRG1.

}, keywords = {DNA Mutational Analysis, Heterozygote, Humans, Mutation, Neutropenia, Pedigree, Vacuolar Proton-Translocating ATPases}, issn = {1098-1004}, doi = {10.1002/humu.22563}, author = {Makaryan, Vahagn and Rosenthal, Elisabeth A and Bolyard, Audrey Anna and Kelley, Merideth L and Below, Jennifer E and Bamshad, Michael J and Bofferding, Kathryn M and Smith, Joshua D and Buckingham, Kati and Boxer, Laurence A and Skokowa, Julia and Welte, Karl and Nickerson, Deborah A and Jarvik, Gail P and Dale, David C} }