Case Report: Association between cyclic neutropenia and SRP54 deficiency.

Autosomal dominant mutations in the signal recognition particle (SRP) 54 gene were recently described in patients with severe congenital neutropenia (SCN). SRP54 deficiency cause a chronic and profound neutropenia with maturation arrest at the promyelocyte stage, occurring in the first months of life. Nearly all reported patients with SRP54 mutations had neutropenia without a cyclic pattern and showed a poor or no response to granulocyte colony-stimulating factor (G-CSF) therapy. We report here an 11-year-old female patient with cyclic neutropenia and recurrent heterozygous p.T117del (c.349_351del) in-frame deletion mutation in SRP54, who showed remarkable therapeutic response to G-CSF treatment. The diagnosis of cyclic pattern of neutropenia was established by acceptable standards. ELANE gene mutation was excluded by using various genetic approaches. The patient described here also had dolichocolon which has not been described before in association with SCN.

Care of patients with inborn errors of immunity in thirty J Project countries between 2004 and 2021.

Introduction: The J Project (JP) physician education and clinical research collaboration program was started in 2004 and includes by now 32 countries mostly in Eastern and Central Europe (ECE). Until the end of 2021, 344 inborn errors of immunity (IEI)-focused meetings were organized by the JP to raise awareness and facilitate the diagnosis and treatment of patients with IEI. Results: In this study, meeting profiles and major diagnostic and treatment parameters were studied. JP center leaders reported patients' data from 30 countries representing a total population of 506 567 565. Two countries reported patients from JP centers (Konya, Turkey and Cairo University, Egypt). Diagnostic criteria were based on the 2020 update of classification by the IUIS Expert Committee on IEI. The number of JP meetings increased from 6 per year in 2004 and 2005 to 44 and 63 in 2020 and 2021, respectively. The cumulative number of meetings per country varied from 1 to 59 in various countries reflecting partly but not entirely the population of the respective countries. Altogether, 24,879 patients were reported giving an average prevalence of 4.9. Most of the patients had predominantly antibody deficiency (46,32%) followed by patients with combined immunodeficiencies (14.3%). The percentages of patients with bone marrow failure and phenocopies of IEI were less than 1 each. The number of patients was remarkably higher that those reported to the ESID Registry in 13 countries. Immunoglobulin (IgG) substitution was provided to 7,572 patients (5,693 intravenously) and 1,480 patients received hematopoietic stem cell therapy (HSCT). Searching for basic diagnostic parameters revealed the availability of immunochemistry and flow cytometry in 27 and 28 countries, respectively, and targeted gene sequencing and new generation sequencing was available in 21 and 18 countries. The number of IEI centers and experts in the field were 260 and 690, respectively. We found high correlation between the number of IEI centers and patients treated with intravenous IgG (IVIG) (correlation coefficient, cc, 0,916) and with those who were treated with HSCT (cc, 0,905). Similar correlation was found when the number of experts was compared with those treated with HSCT. However, the number of patients treated with subcutaneous Ig (SCIG) only slightly correlated with the number of experts (cc, 0,489) and no correlation was found between the number of centers and patients on SCIG (cc, 0,174). Conclusions: 1) this is the first study describing major diagnostic and treatment parameters of IEI care in countries of the JP; 2) the data suggest that the JP had tremendous impact on the development of IEI care in ECE; 3) our data help to define major future targets of JP activity in various countries; 4) we suggest that the number of IEI centers and IEI experts closely correlate to the most important treatment parameters; 5) we propose that specialist education among medical professionals plays pivotal role in increasing levels of diagnostics and adequate care of this vulnerable and still highly neglected patient population; 6) this study also provides the basis for further analysis of more specific aspects of IEI care including genetic diagnostics, disease specific prevalence, newborn screening and professional collaboration in JP countries.

Novel STAT-3 gain-of-function variant with hypogammaglobulinemia and recurrent infection phenotype.

Signal transducer and activator of transcription 3 (STAT-3) gain-of-function (GOF) syndrome is an early-onset monogenic inborn error of immunity characterized by multi-organ autoimmune disorders, growth failure and lymphoproliferation. We describe that STAT-3 GOF syndrome may be presented with hypogammaglobulinemia and recurrent severe upper and lower respiratory tract infections. In addition, the patient had lymphoproliferation, short stature and interstitial lung disease. Chest computerized tomography examinations showed mild bronchiectasis with areas of non-fibrosing alveolar-interstitial disease and maldevelopment of bilateral first ribs. Using Sanger sequencing, we revealed a novel c.508G>C, p.D170H STAT-3 variant affecting the coiled coil domain of STAT-3. Functional studies confirmed that p.D170H was a GOF variant, as shown by increased phosphorylated STAT-3 (pSTAT-3) and STAT-3 transcriptional activity. Our observation suggests that STAT-3 GOF syndrome can manifest in early childhood with hypogammaglobulinemia and recurrent severe respiratory tract infections. We suggest that patients with lymphoproliferation, hypogammaglobulinemia and severe recurrent infections should be screened for STAT-3 variants, even if autoimmune manifestations are missing.

Recurrent, Severe Aphthous Stomatitis and Mucosal Ulcers as Primary Manifestations of a Novel STAT1 Gain-of-Function Mutation.

Chronic mucocutaneous candidiasis (CMC) characterized by persistent and recurrent Candida infection of the skin, nails, and the mucosa membranes has been proposed as the major infectious phenotype in patients with gain-of-function mutation of signal transducer and activator of transcription 1 (STAT1) 1. However, viral infections caused mostly by herpesviruses, and a broad range of autoimmune disorders may also be part of the clinical phenotype. We report here on a 31 years old female patient suffering from severe mucosal aphthous mucositis and ulcers and recurrent herpes simplex for decades. We found a previously unknown heterozygous sequence variant in STAT1 (c.1219C>G; L407V) affecting the DNA-binding domain of the protein in the patient and her 4 years old daughter. We found this mutation gain-of-function (GOF) by using immunoblot and luciferase assays. We detected low proportion of IL-17A-producing CD4+ T cell lymphocytes by using intracellular staining and flow cytometry. Candida-induced secretion of IL-17A and IL-22 by mononuclear cells from the patient was markedly decreased compared to controls. These data suggest that the novel mutant allele may result in impaired differentiation of CD4+ T cells to CD4+/IL-17+ cells. The clinical phenotype of the disease in this patient was unique as it was dominated primarily by severe aphthous stomatitis and ulcerative esophagitis and only partly by typical CMC resulting in diagnostic delay. We suggest that patients with severe recurrent aphthous stomatitis and esophagitis should be evaluated for STAT1 GOF mutation. Based on the broad clinical spectrum of the disease, we also suggest that CMC and CMC disease may not be an appropriate term to define clinically STAT1 GOF mutation.

Tolerability of subcutaneous immunoglobulin 20%, Ig20Gly, in pediatric patients with primary immunodeficiencies.

AIM: To assess Ig20Gly tolerability in pediatric patients with primary immunodeficiencies. PATIENTS & METHODS: Infusion parameters and tolerability were analyzed in pediatric patients (aged 2-5 years [n = 6], 6-11 years [n = 22] and 12-17 years [n = 22]) receiving Ig20Gly in two Phase II/III trials. RESULTS: Of 2624 Ig20Gly infusions, >99% did not require any rate reduction, interruption or discontinuation due to adverse events (AEs). Median maximum infusion rates and volumes/site were higher in patients 12-17 years of age (30 ml/h/site; 30 ml/site) versus 6-11 years (20 ml/h/site; 15 ml/site) and 2-5 years (18 ml/h/site; 14 ml/site). Rates of causally related systemic and local AEs (0.009 and 0.063 AEs/infusion) were low. CONCLUSION: Ig20Gly infused at relatively high rates and volumes was well tolerated in children.

[Cutaneous manifestations in primary immunodeficiency diseases]. / Az elsodleges immunhiány-betegségek bormanifesztációi.

Primary immunodeficiency diseases (PIDs) are inherited, genetic disorders. The majority of PIDs are diagnosed in infancy or early childhood, but manifestation in adulthood may also occur. Frequent, recurrent and prolonged infections, which respond poorly to treatment may be heralding signs. PID patients may have increased suspectibility to infections, that mostly affect the sino-pulmonary and intestinal tracts and the skin. PIDs are also frequently associated with autoimmune and inflammatory disorders. Cutaneous manifestations affect 40% to 70% of patients with diagnosed PID. Bacterial and fungal infections of the skin, recurrent pyogen abscesses are common complications. Severe atopy, eczema and erythroderma occurring early in childhood should raise awareness of PID. Cutaneous granulomas, pigment changes and dysplasia of skin, hair, and nails can also be seen frequently in some of these conditions. Here we overview the most frequent dermatological diseases occuring in patients with PID. Orv Hetil. 2018; 159(23): 937-947.

Heterozygous STAT1 gain-of-function mutations underlie an unexpectedly broad clinical phenotype.

Since their discovery in patients with autosomal dominant (AD) chronic mucocutaneous candidiasis (CMC) in 2011, heterozygous STAT1 gain-of-function (GOF) mutations have increasingly been identified worldwide. The clinical spectrum associated with them needed to be delineated. We enrolled 274 patients from 167 kindreds originating from 40 countries from 5 continents. Demographic data, clinical features, immunological parameters, treatment, and outcome were recorded. The median age of the 274 patients was 22 years (range, 1-71 years); 98% of them had CMC, with a median age at onset of 1 year (range, 0-24 years). Patients often displayed bacterial (74%) infections, mostly because of Staphylococcus aureus (36%), including the respiratory tract and the skin in 47% and 28% of patients, respectively, and viral (38%) infections, mostly because of Herpesviridae (83%) and affecting the skin in 32% of patients. Invasive fungal infections (10%), mostly caused by Candida spp. (29%), and mycobacterial disease (6%) caused by Mycobacterium tuberculosis, environmental mycobacteria, or Bacille Calmette-Guérin vaccines were less common. Many patients had autoimmune manifestations (37%), including hypothyroidism (22%), type 1 diabetes (4%), blood cytopenia (4%), and systemic lupus erythematosus (2%). Invasive infections (25%), cerebral aneurysms (6%), and cancers (6%) were the strongest predictors of poor outcome. CMC persisted in 39% of the 202 patients receiving prolonged antifungal treatment. Circulating interleukin-17A-producing T-cell count was low for most (82%) but not all of the patients tested. STAT1 GOF mutations underlie AD CMC, as well as an unexpectedly wide range of other clinical features, including not only a variety of infectious and autoimmune diseases, but also cerebral aneurysms and carcinomas that confer a poor prognosis.

Nijmegen Breakage Syndrome: Clinical and Immunological Features, Long-Term Outcome and Treatment Options - a Retrospective Analysis.

PURPOSE: Nijmegen Breakage Syndrome (NBS) is a rare inherited condition, characterized by microcephaly, chromosomal instability, immunodeficiency, and predisposition to malignancy. This retrospective study, characterizing the clinical and immunological status of patients with NBS at time of diagnosis, was designed to assess whether any parameters were useful in disease prognosis, and could help determine patients qualified for hematopoietic stem cell transplantation. METHODS: The clinical and immunological characteristics of 149 NBS patients registered in the online database of the European Society for Immune Deficiencies were analyzed. RESULTS: Of the 149 NBS patients, 91 (61%), of median age 14.3 years, remained alive at the time of analysis. These patients were clinically heterogeneous, with variable immune defects, ranging from negligible to severe dysfunction. Humoral deficiencies predisposed NBS patients to recurrent/chronic respiratory tract infections and worsened long-term clinical prognosis. Eighty malignancies, most of lymphoid origin (especially non-Hodgkin's lymphomas), were diagnosed in 42% of patients, with malignancy being the leading cause of death in this cohort. Survival probabilities at 5, 10, 20 and 30 years of age were 95, 85, 50 and 35%, respectively, and were significantly lower in patients with than without malignancies. CONCLUSIONS: The extremely high incidence of malignancies, mostly non-Hodgkin's lymphomas, was the main risk factor affecting survival probability in NBS patients. Because treatment of NBS is very difficult and frequently unsuccessful, the search for an alternative medical intervention such as hematopoietic stem cell transplantation is of great clinical importance.

DOCK8 deficiency: clinical and immunological phenotype and treatment options - a review of 136 patients.

Mutations in DOCK8 result in autosomal recessive Hyper-IgE syndrome with combined immunodeficiency (CID). However, the natural course of disease, long-term prognosis, and optimal therapeutic management have not yet been clearly defined. In an international retrospective survey of patients with DOCK8 mutations, focused on clinical presentation and therapeutic measures, a total of 136 patients with a median follow-up of 11.3 years (1.3-47.7) spanning 1693 patient years, were enrolled. Eczema, recurrent respiratory tract infections, allergies, abscesses, viral infections and mucocutaneous candidiasis were the most frequent clinical manifestations. Overall survival probability in this cohort [censored for hematopoietic stem cell transplantation (HSCT)] was 87 % at 10, 47 % at 20, and 33 % at 30 years of age, respectively. Event free survival was 44, 18 and 4 % at the same time points if events were defined as death, life-threatening infections, malignancy or cerebral complications such as CNS vasculitis or stroke. Malignancy was diagnosed in 23/136 (17 %) patients (11 hematological and 9 epithelial cancers, 5 other malignancies) at a median age of 12 years. Eight of these patients died from cancer. Severe, life-threatening infections were observed in 79/136 (58 %); severe non-infectious cerebral events occurred in 14/136 (10 %). Therapeutic measures included antiviral and antibacterial prophylaxis, immunoglobulin replacement and HSCT. This study provides a comprehensive evaluation of the clinical phenotype of DOCK8 deficiency in the largest cohort reported so far and demonstrates the severity of the disease with relatively poor prognosis. Early HSCT should be strongly considered as a potential curative measure.

Gene therapy for Wiskott-Aldrich syndrome--long-term efficacy and genotoxicity.

Wiskott-Aldrich syndrome (WAS) is characterized by microthrombocytopenia, immunodeficiency, autoimmunity, and susceptibility to malignancies. In our hematopoietic stem cell gene therapy (GT) trial using a γ-retroviral vector, 9 of 10 patients showed sustained engraftment and correction of WAS protein (WASP) expression in lymphoid and myeloid cells and platelets. GT resulted in partial or complete resolution of immunodeficiency, autoimmunity, and bleeding diathesis. Analysis of retroviral insertion sites revealed >140,000 unambiguous integration sites and a polyclonal pattern of hematopoiesis in all patients early after GT. Seven patients developed acute leukemia [one acute myeloid leukemia (AML), four T cell acute lymphoblastic leukemia (T-ALL), and two primary T-ALL with secondary AML associated with a dominant clone with vector integration at the LMO2 (six T-ALL), MDS1 (two AML), or MN1 (one AML) locus]. Cytogenetic analysis revealed additional genetic alterations such as chromosomal translocations. This study shows that hematopoietic stem cell GT for WAS is feasible and effective, but the use of γ-retroviral vectors is associated with a substantial risk of leukemogenesis.

Analysis of lyso-globotriaosylsphingosine in dried blood spots.

Recently, lyso-globotriaosylsphingosine (lyso-Gb3) was found to be elevated in plasma of treatment naive male patients and some female patients with Fabry Disease (FD). This study tested whether lyso-Gb3 could be analyzed in dried blood spots (DBS) from filter cards and whether concentrations are elevated in newborn infants with FD. Lyso-Gb3 concentrations were analyzed in DBS following extraction using a novel HPLC-mass spectrometry (MS)/MS method. Lyso-Gb3 levels in DBS were above the lower limit of quantitation (0.28 ng/mL) in 5/17 newborn FD infants (16 males; range: 1.02-8.81 ng/mL), but in none of the newborn controls, in all 13 patients (4 males) with classic FD (range: 2.06-54.1 ng/mL), in 125/159 Taiwanese individuals with symptomatic or asymptomatic FD who carry the late onset α-galactosidase A (GLA) mutation c.936+919G>A (IVS4+919G>A) (3.75±0.69 ng/mL; range: 0.418-3.97 ng/mL) and in 20/29 healthy controls (0.77±0.24 ng/mL; range: 0.507-1.4 ng/mL). The HPLC-MS/MS method for analysis of lyso-Gb3 is robust and yields reproducible results in DBS in patients with FD. However, concentrations of lyso-Gb3 were below the limit of quantitation in most newborn infants with FD rendering this approach not suitable for newborn screening. In addition, most females with the late onset mutation have undetectable lyso-Gb3 concentrations.

IgM+IgD+CD27+ B cells are markedly reduced in IRAK-4-, MyD88-, and TIRAP- but not UNC-93B-deficient patients.

We studied the distribution of peripheral B-cell subsets in patients deficient for key factors of the TLR-signaling pathways (MyD88, TIRAP/MAL, IL-1 receptor-associated kinase 4 [IRAK-4], TLR3, UNC-93B, TRIF). All TLRs, except TLR3, which signals through the TRIF adaptor, require MyD88 and IRAK-4 to mediate their function. TLR4 and the TLR2 heterodimers (with TLR1, TLR6, and possibly TLR10) require in addition the adaptor TIRAP, whereas UNC-93B is needed for the proper localization of intracellular TLR3, TLR7, TLR8, and TLR9. We found that IgM(+)IgD(+)CD27(+) but not switched B cells were strongly reduced in MyD88-, IRAK-4-, and TIRAP-deficient patients. This defect did not appear to be compensated with age. However, somatic hypermutation of Ig genes and heavy-chain CDR3 size distribution of IgM(+)IgD(+)CD27(+) B cells were not affected in these patients. In contrast, the numbers of IgM(+)IgD(+)CD27(+) B cells were normal in the absence of TLR3, TRIF, and UNC-93B, suggesting that UNC-93B-dependent TLRs, and notably TLR9, are dispensable for the presence of this subset in peripheral blood. Interestingly, TLR10 was found to be expressed at greater levels in IgM(+)IgD(+)CD27(+) compared with switched B cells in healthy patients. Hence, we propose a role for TIRAP-dependent TLRs, possibly TLR10 in particular, in the development and/or maintenance of IgM(+)IgD(+)CD27(+) B cells in humans.

Renal outcomes of agalsidase beta treatment for Fabry disease: role of proteinuria and timing of treatment initiation.

BACKGROUND: The purpose of this study was to identify determinants of renal disease progression in adults with Fabry disease during treatment with agalsidase beta. METHODS: Renal function was evaluated in 151 men and 62 women from the Fabry Registry who received agalsidase beta at an average dose of 1 mg/kg/2 weeks for at least 2 years. Patients were categorized into quartiles based on slopes of estimated glomerular filtration rate (eGFR) during treatment. Multivariate logistic regression analyses were used to identify factors associated with renal disease progression. RESULTS: Men within the first quartile had a mean eGFR slope of -0.1 mL/min/1.73m(2)/year, whereas men with the most rapid renal disease progression (Quartile 4) had a mean eGFR slope of -6.7 mL/min/1.73m(2)/year. The risk factor most strongly associated with renal disease progression was averaged urinary protein:creatinine ratio (UP/Cr) ≥1 g/g (odds ratio 112, 95% confidence interval (95% CI) 4-3109, P = 0.0054). Longer time from symptom onset to treatment was also associated with renal disease progression (odds ratio 19, 95% CI 2-184, P = 0.0098). Women in Quartile 4 had the highest averaged UP/Cr (mean 1.8 g/g) and the most rapid renal disease progression: (mean slope -4.4 mL/min/1.73m(2)/year). CONCLUSIONS: Adults with Fabry disease are at risk for progressive loss of eGFR despite enzyme replacement therapy, particularly if proteinuria is ≥1 g/g. Men with little urinary protein excretion and those who began receiving agalsidase beta sooner after the onset of symptoms had stable renal function. These findings suggest that early intervention may lead to optimal renal outcomes.

Nijmegen breakage syndrome complicated with primary cutaneous tuberculosis.

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosomal instability syndrome characterized by severe immunodeficiency, growth retardation, microcephaly, a distinct facial appearance, and a high predisposition to lymphoid malignancy. We report a 7-year-old white girl with NBS associated with cutaneous tuberculosis. The patient presented with multiple red-brown, centrally scaring plaques on the leg and had neither pulmonary nor systemic manifestation of tuberculosis. Polymerase chain reaction testing using Mycobacterium genus- and Mycobacterium tuberculosis species-specific primers confirmed the clinical diagnosis of cutaneous tuberculosis. This is the first report describing the simultaneous presentation of NBS and cutaneous tuberculosis.

Genetic characteristics of eighty-seven patients with the Wiskott-Aldrich syndrome.

The Wiskott-Aldrich syndrome (WAS) is an X-linked recessive immune deficiency disorder characterized by thrombocytopenia, small platelet size, eczema, recurrent infections, and increased risk of autoimmune disorders and malignancies. WAS is caused by mutations in the WASP gene which encodes WASP, a 502-amino acid protein. WASP plays a critical role in actin cytoskeleton organization and signalling, and functions of immune cells. We present here the results of genetic analysis of patients with WAS from eleven Eastern and Central European (ECE) countries and Turkey. Clinical and haematological information of 87 affected males and 48 carrier females from 77 WAS families were collected. The WASP gene was sequenced from genomic DNA of patients with WAS, as well as their family members to identify carriers. In this large cohort, we identified 62 unique mutations including 17 novel sequence variants. The mutations were scattered throughout the WASP gene and included single base pair changes (17 missense and 11 nonsense mutations), 7 small insertions, 18 deletions, and 9 splice site defects. Genetic counselling and prenatal diagnosis were applied in four affected families. This study was part of the J Project aimed at identifying genetic basis of primary immunodeficiency disease in ECE countries. This report provides the first comprehensive overview of the molecular genetic and demographic features of WAS in ECE.

Stem-cell gene therapy for the Wiskott-Aldrich syndrome.

The Wiskott-Aldrich syndrome (WAS) is an X-linked recessive primary immunodeficiency disorder associated with thrombocytopenia, eczema, and autoimmunity. We treated two patients who had this disorder with a transfusion of autologous, genetically modified hematopoietic stem cells (HSC). We found sustained expression of WAS protein expression in HSC, lymphoid and myeloid cells, and platelets after gene therapy. T and B cells, natural killer (NK) cells, and monocytes were functionally corrected. After treatment, the patients' clinical condition markedly improved, with resolution of hemorrhagic diathesis, eczema, autoimmunity, and predisposition to severe infection. Comprehensive insertion-site analysis showed vector integration that targeted multiple genes controlling growth and immunologic responses in a persistently polyclonal hematopoiesis. (Funded by Deutsche Forschungsgemeinschaft and others; German Clinical Trials Register number, DRKS00000330.).

Prognostic indicators of renal disease progression in adults with Fabry disease: natural history data from the Fabry Registry.

BACKGROUND AND OBJECTIVES: These analyses were designed to characterize renal disease progression in untreated adults with Fabry disease. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Data from the Fabry Registry for 462 untreated adults (121 men and 341 women) who had at least two estimated GFR (eGFR) values over a span of ≥12 months before starting enzyme replacement therapy were included. RESULTS: Most men (86 of 121, 71%) had more rapid loss of kidney function than the normal adult population (loss of eGFR > -1 ml/min per 1.73 m(2) per year), whereas fewer women (133 of 341, 39%) had rapid loss of kidney function. Patients with rapid progression had significantly higher mean averaged urinary protein to urinary creatinine ratios (UP/Cr) than patients with slower progression (1.5 versus 0.2 for men; 1.4 versus 0.5 for women; P < 0.0001). Patients were grouped into quartiles based on averaged UP/Cr; renal function in men declined more rapidly with higher UP/Cr, with the steepest declines observed in men with UP/Cr > 1.5 (mean eGFR slope, -5.6 ml/min per 1.73 m(2) per year; n = 30). eGFR slope declined more slowly in women, with the steepest declines observed in women with UP/Cr > 1.2 (mean eGFR slope, -1.3 ml/min per 1.73 m(2) per year; n = 85). Regression models of eGFR slope indicated that UP/Cr is the most important indicator of renal disease progression in adult Fabry patients. In women, lower baseline eGFR and age were also associated with renal disease progression. Women who had clinical events had more rapid loss of kidney function. CONCLUSIONS: Urinary protein excretion is strongly associated with renal disease progression in men and women with Fabry disease.

Hematologically important mutations: X-linked chronic granulomatous disease (third update).

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. The disease is caused by a lack of superoxide production by the leukocyte enzyme NADPH oxidase. Superoxide is used to kill phagocytosed micro-organisms in neutrophils, eosinophils, monocytes and macrophages. The leukocyte NADPH oxidase is composed of five subunits, of which the enzymatic component is gp91-phox, also called Nox2. This protein is encoded by the CYBB gene on the X chromosome. Mutations in this gene are found in about 70% of all CGD patients. This article lists all mutations identified in CYBB in the X-linked form of CGD. Moreover, apparently benign polymorphisms in CYBB are also given, which should facilitate the recognition of future disease-causing mutations.