MATERIALS AND METHODS: HbE activates a cryptic splice site that produces non-functional mRNAs. Hb South Florida is a rare beta-hemoglobin variant, and its interactions with other beta-thalassemia alleles have not been reported. IVS1-1 is a Mediterranean mutation that affects mRNA processing giving rise to beta(o)-thalassemia.
RESULTS AND DISCUSSION: Fifteen mutations along the beta-globin gene complex were analyzed using the amplification refractory mutation system. Hb South Florida was identified by direct sequencing using genomic DNA.
CONCLUSION: The affected child with HbE/IVS1-1 produced a beta-thalassemia major phenotype. Compound heterozygosity for Hb South Florida/IVS1-1 produced a beta-thalassemia carrier phenotype in the mother.
PATIENTS AND METHODS: We report two siblings of a healthy but consanguineous Malaysian family presenting with severe short stature caused by CPHD with a variable phenotype. Importantly, at the beginning the girl presented with isolated GHD, whereas the boy was hypothyroid. As the most common gene alterations responsible for CPHD are within either the PROP-1- or the POU1F1- (PIT-1)-gene these two genes were further studied.
RESULTS: Subsequent sequencing of the six exons of the POU1F1-gene allowed the identification of a new N-terminal mutation (Q4ter) in these two children. A substitution of C to T induced a change from a glutamine (CAA) to a stop codon (TAA) in exon 1 of the PIT-1 protein. Both affected children were homozygous for the mutation, whereas the mother and father were heterozygous.
CONCLUSION: We describe two children with autosomal recessive inherited CPHD caused by a new N-terminal located mutation within the PUO1F1-gene. The clinical history of these two children underline the phenotypic variability and support the fact that children with any isolated and/or combined PHD need to be closely followed as at an any time other hormonal deficiencies may occur. In addition, molecular analysis of the possible genes involved might be most helpful for the future follow-up.