Prevalence rates for ectodermal dysplasia syndromes.

BACKGROUND: Ectodermal dysplasias (EDs) are a heterogeneous group of genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. There are currently 49 recognized EDs with molecularly confirmed etiology. The EDs are very rare disorders, individually and in aggregate. Very little is published regarding the prevalence of these rare disorders. As a result of the genomics revolution, rare diseases have emerged as a global health priority. The various disabilities arising from rare disorders, as well as diagnostic and treatment uncertainty, have been demonstrated to have detrimental effects on the health, psychosocial, and economic aspects of families affected by rare disorders. Contemporary research methodologies and databases can address what have been historic challenges encountered when conducting research on rare diseases. OBJECTIVE: In this study, we aim to ascertain period prevalence rates for several of the more common ectodermal dysplasia syndromes, by querying a large multicenter database of electronic health records, Oracle Real-World Data. METHODS: For each of the included ectodermal dysplasia syndromes a clinical definition was developed by a committee of international experts with interests in EDs. The clinical definitions were based upon a combination of clinical features and designated by ICD-9 and ICD-10 codes. The January 2023 version of the Oracle Real-World Data database was queried for medical records that coincided with the clinical definitions. For our study, there were 64,523,460 individual medical records queried. RESULTS: Period prevalence rates were calculated for the following ED disorders: hypohidrotic ectodermal dysplasia, found to be 2.99 per 100,000; ectodermal dysplasia and immunodeficiency 1, 0.23 per 100,000; Clouston syndrome, 0.15 per 100,000; ectrodactyly ectodermal dysplasia and cleft lip/palate syndrome, 0.61 per 100,000; ankyloblepharon-ectodermal defects-cleft lip/palate syndrome, 0.36 per 100,000; focal dermal hypoplasia, 0.10 per 100,000; and incontinentia pigmenti, 0.88 per 100,000. CONCLUSION: This study established estimated period prevalence rates for several of the ectodermal dysplasia syndromes, and it demonstrated the feasibility of utilizing large multicenter databases of electronic health records, such as Oracle Real World Data.

Mechanisms of genotype-phenotype correlation in autosomal dominant anhidrotic ectodermal dysplasia with immune deficiency.

BACKGROUND: Autosomal dominant anhidrotic ectodermal dysplasia with immune deficiency (AD EDA-ID) is caused by heterozygous point mutations at or close to serine 32 and serine 36 or N-terminal truncations in IκBα that impair its phosphorylation and degradation and thus activation of the canonical nuclear factor κ light chain enhancer of activated B cells (NF-κB) pathway. The outcome of hematopoietic stem cell transplantation is poor in patients with AD EDA-ID despite achievement of chimerism. Mice heterozygous for the serine 32I mutation in IκBα have impaired noncanonical NF-κB activity and defective lymphorganogenesis. OBJECTIVE: We sought to establish genotype-phenotype correlation in patients with AD EDA-ID. METHODS: A disease severity scoring system was devised. Stability of IκBα mutants was examined in transfected cells. Immunologic, biochemical, and gene expression analyses were performed to evaluate canonical and noncanonical NF-κB signaling in skin-derived fibroblasts. RESULTS: Disease severity was greater in patients with IκBα point mutations than in those with truncation mutations. IκBα point mutants were expressed at significantly higher levels in transfectants compared with truncation mutants. Canonical NF-κB-dependent IL-6 secretion and upregulation of the NF-κB subunit 2/p100 and RELB proto-oncogene, NF-κB subunit (RelB) components of the noncanonical NF-κB pathway were diminished significantly more in patients with point mutations compared with those with truncations. Noncanonical NF-κB-driven generation of the transcriptionally active p100 cleavage product p52 and upregulation of CCL20, intercellular adhesion molecule 1 (ICAM1), and vascular cell adhesion molecule 1 (VCAM1), which are important for lymphorganogenesis, were diminished significantly more in LPS plus α-lymphotoxin ß receptor-stimulated fibroblasts from patients with point mutations compared with those with truncations. CONCLUSIONS: IκBα point mutants accumulate at higher levels compared with truncation mutants and are associated with more severe disease and greater impairment of canonical and noncanonical NF-κB activity in patients with AD EDA-ID.