A novel double hemizygous BTK mutation in a boy presenting with Pseudomonas skin abscesses.

Skin manifestations can serve as critical clues for early diagnosis of inborn errors of immunity. We report a patient with a double novel mutation in the BTK gene, who presented with skin abscesses caused by Pseudomonas aeruginosa. This case illustrates the importance of immune evaluation in patients with therapy-resistant skin lesions.

WNT Signaling Perturbations Underlie the Genetic Heterogeneity of Robinow Syndrome.

Locus heterogeneity characterizes a variety of skeletal dysplasias often due to interacting or overlapping signaling pathways. Robinow syndrome is a skeletal disorder historically refractory to molecular diagnosis, potentially stemming from substantial genetic heterogeneity. All current known pathogenic variants reside in genes within the noncanonical Wnt signaling pathway including ROR2, WNT5A, and more recently, DVL1 and DVL3. However, ∼70% of autosomal-dominant Robinow syndrome cases remain molecularly unsolved. To investigate this missing heritability, we recruited 21 families with at least one family member clinically diagnosed with Robinow or Robinow-like phenotypes and performed genetic and genomic studies. In total, four families with variants in FZD2 were identified as well as three individuals from two families with biallelic variants in NXN that co-segregate with the phenotype. Importantly, both FZD2 and NXN are relevant protein partners in the WNT5A interactome, supporting their role in skeletal development. In addition to confirming that clustered -1 frameshifting variants in DVL1 and DVL3 are the main contributors to dominant Robinow syndrome, we also found likely pathogenic variants in candidate genes GPC4 and RAC3, both linked to the Wnt signaling pathway. These data support an initial hypothesis that Robinow syndrome results from perturbation of the Wnt/PCP pathway, suggest specific relevant domains of the proteins involved, and reveal key contributors in this signaling cascade during human embryonic development. Contrary to the view that non-allelic genetic heterogeneity hampers gene discovery, this study demonstrates the utility of rare disease genomic studies to parse gene function in human developmental pathways.

The Relationship Between Endothelial Nitric Oxide Synthase Gene (NOS3) Polymorphisms, NOS3 Expression, and Varicocele.

BACKGROUND: Varicocele is an abnormal enlargement of the pampiniform venous plexus in the scrotum. Varicocele is the most common cause of secondary male infertility. Nitric oxide (NO), which has a role on varicocele pathophysiology, is synthesized by endothelial nitric oxide synthase gene (NOS3). OBJECTIVE: In our study, we aimed to explain the relationship between varicocele, three common NOS3 polymorphisms (T-786C, G894T, 4b/a), and NOS3 mRNA expression levels. METHODS: We investigated NOS3 T-786C, G894T, and 4b/a polymorphisms in 102 patients with varicocele and 100 healthy controls. Twenty-four patients and 17 controls were chosen for expression studies based on polymorphism subgroupings. Subgroup 1 includes patients who have no minor allele polymorphisms, and subgroups 2, 3, and 4 have T-786C, G894T, and 4b/a polymorphisms, respectively. RESULTS: The 4b/a polymorphism demonstrated significantly elevated levels in both allele and genotype analysis in the control group compared to the patient group. The G894T polymorphism was statistically elevated for genotypic frequencies in the patient group compared to the control group, but this finding did not extend to allelic frequencies. There were no statistically significant differences in either the allelic or genotypic frequencies between patients and control groups for the T-786C polymorphism. When patient and control expression levels were compared without considering the subgroups, the NOS3 expression level was found to be statistically higher in the patient group. There were no statistically significant differences in the patient and control group expression levels when stratified by subgroup, nor was there any effect of the polymorphisms under study on expression levels. CONCLUSIONS: The 4b/a polymorphism may have a protective effect for varicocelem and G894T polymorphism may contribute to varicocele occurrence by lowering the level of NO. The higher NOS3 expression levels in the patient group may be a kind of dilator compensatory mechanism to protect vascular anatomy in varicocele.

Unilateral cataract and vitreoretinopathy in a case with klippel-trenaunay syndrome.

Purpose. We present a case with Klippel-Trenaunay (KT) syndrome that had unilateral mature cataract and vitreoretinopathy. Case Report. A 17-year-old boy with KT syndrome presented to the clinic of ophthalmology for low vision in the right eye. His best corrected visual acuity (BCVA) was hand motion in the right eye and 20/20 in the left eye. Anterior segment examination revealed mature cataract in the right. During the physical examination, port-wine stains were noted over right side of his face, ankle, and toes. He had asymmetric face and his head was larger on the right side. Leg lengths were symmetrical, although he had skin hypertrophy. Cranial magnetic resonance imaging studies showed cortical atrophy discordant to his age, asymmetric vascular dilatations in the right hemisphere, hypertrophy in the right periorbital soft tissue, and choroidal plexus. The patient received an uncomplicated cataract surgery. His BCVA in the right eye improved to 20/200 after the surgery. After removing cataractous lens, we were able to examine the fundus that revealed severe vitreoretinopathy and choroidal hemangioma. Conclusion. This case emphasizes the importance of prompt ophthalmic examination in patients with KT syndrome.