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Fanconi-Bickel syndrome (FBS) is a rare autosomal recessive disease, resulting from mutations in the SLC2A2 gene, causing impaired glucose transporter 2 protein transporter protein function, impaired glucose and galactose utilisation, hepatorenal glycogen accumulation and organ dysfunction. Clinical features include failure to thrive, hepatomegaly, rickets, short stature and delayed puberty. Therapy includes electrolyte supplementation and uncooked cornstarch. We present a 15-year-old boy diagnosed with FBS in infancy. Growth velocity was normal on standard treatment until age 8.5 years, at which time growth failure led to a diagnosis of acquired growth hormone (GH) deficiency. Initiation of recombinant human GH (rhGH) replacement of 0.25 μg/kg/week resulted in marked improvement in growth velocity and height. While short stature is expected in FBS, growth velocity that falls below the normal range despite adequate therapy should prompt further evaluation. Our case suggests that acquired GH deficiency can arise in FBS and benefits from rhGH therapy., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

We have identified a novel Iroquois (Iro) gene, iro7, in zebrafish. iro7 is expressed during gastrulation along with iro1 in a compartment of the dorsal ectoderm that includes the prospective midbrain-hindbrain domain, the adjacent neural crest and the trigeminal placodes in the epidermis. The iro1 and iro7 expression domain is expanded in headless and masterblind mutants, which are characterized by exaggerated Wnt signaling. Early expansion of iro1 and iro7 expression in these mutants correlates with expansion of the midbrain-hindbrain boundary (MHB) domain, the neural crest and trigeminal neurons, raising the possibility that iro1 and iro7 have a role in determination of these ectodermal derivatives. A knockdown of iro7 function revealed that iro7 is essential for the determination of neurons in the trigeminal placode. In addition, a knockdown of both iro1 and iro7 genes uncovered their essential roles in neural crest development and establishment of the isthmic organizer at the MHB. These results suggest a new role for Iro genes in establishment of an ectodermal compartment after Wnt signaling in vertebrate development. Furthermore, analysis of activator or repressor forms of iro7 suggests that iro1 and iro7 are likely to function as repressors in establishment of the isthmic organizer and neural crest, and Iro genes may have dual functions as repressors and activators in neurogenesis.

Clostridial myonecrosis (CM) is a rare infection that usually arises after traumatic injury. Spontaneous or nontraumatic CM is even more rare and has been described in association with colorectal malignancy. These infections carry a high mortality rate and require urgent surgical intervention and intensive antibiotic therapy. This report describes a patient who presented with nontraumatic CM of the lower extremity in association with adenocarcinoma of the cecum.

A screen for developmentally regulated genes was conducted in the zebrafish, a system offering substantial advantages for the study of the molecular genetics of vertebrate embryogenesis. Clones from a normalized cDNA library from early somitogenesis stages were picked randomly and tested by high-throughput in situ hybridization for restricted expression in at least one of four stages of development. Among 2765 clones that were screened, a total of 347 genes with patterns judged to be restricted were selected. These clones were subjected to partial sequence analysis, allowing recognition of functional motifs in 163 among them. In addition, a portion of the clones were mapped with the aid of the LN54 radiation hybrid panel. The usefulness of the in situ hybridization screening approach is illustrated by describing several new markers for the characteristic structure in the fish embryo named the yolk syncytial layer, and for different regions of the developing brain.