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Background: Heterozygous loss of function mutations in GH1 are a cause of autosomal dominant isolated growth hormone deficiency (GHD) or IGHD type II. However, this condition is rare and a genotype/phenotype association is often based on single case or pedigree reports. Clinical Case: The male proband was born at 38 weeks following an uncomplicated pregnancy, birthweight 2585 gm (˗1.3SD), length 43 cm (˗2.7SD). At 20 months old: length ˗3.2SD, weight/length 16%. Peak growth hormone (GH) levels 4.42 ng/mL and 3.2 ng/mL following clonidine and arginine stimulation, respectively; cortrosyn-stimulated cortisol was 41.4 mcg/dL. Prolactin was 61.2 ng/mL (reference range 2.6 to 13.1 ng/mL); T4 and TSH levels were normal. Magnetic resonance imaging showed a flattened anterior pituitary gland, consistent with empty sella, with normal bright spot. He has had an intermittent and variable response to GH treatment due to noncompliance; recent recorded height was ˗3.6SD at 13.9 and he was early pubertal. Father had a history of childhood growth hormone treatment and is 151 cm tall, 2 paternal aunts did not receive treatment and are 145 cm tall, 3 children of these aunts are diagnosed with GHD. There is no maternal family history of GHD; mother is 155 cm. Proband testing revealed heterozygous GH1 c.291 + 34G>C (EGL Genetics), classified as a variant of unknown significance; father was also found to have this variant, mother was negative. Genetic testing for of additional family members is under consideration. Conclusion: Nine of 96 heterozygous GH1 variants are located in intron 3. Two have been classified as pathogenic and are predicted to cause exon skipping. Our proband’s variant cannot be considered a canonical splice site or in a mutational hot spot but has extremely low frequency in population databases. Functional studies clan clarify if our proband’s variant results in a 17.5 kDa GH isoform and dominant negative effect on full length GH production with potential detrimental effects on other anterior pituitary hormones. We present the second GHD pedigree with GH1 c.291 + 34G>C mutation. As in the previous report (1), no other hormone deficiencies are identified, despite the appearance of an empty sella for our proband. Reference: (1) Cho SY, Ki, CS, Park, HD, et al. Genetic investigation of patients with undetectable peaks of growth hormone after two provocation tests. Clin Endocrinol 2013; 78: 317-20.

Background Polyploidy is well studied from a genetic and genomic perspective, but the morphological, anatomical, and physiological consequences of polyploidy remain relatively uncharacterized. Whether these potential changes bear on functional integration or are idiosyncratic remains an open question. Repeated allotetraploid events and multiple genomic combinations as well as overlapping targets of artificial selection make the Brassica triangle an excellent system for exploring variation in the connection between plant structure (anatomy and morphology) and function (physiology). We examine phenotypic integration among structural aspects of leaves including external morphology and internal anatomy with leaf-level physiology among several species of Brassica. We compare diploid and allotetraploid species to ascertain patterns of phenotypic correlations among structural and functional traits and test the hypothesis that allotetraploidy results in trait disintegration allowing for transgressive phenotypes and additional evolutionary and crop improvement potential. Results Among six Brassica species, we found significant effects of species and ploidy level for morphological, anatomical and physiological traits. We identified three suites of intercorrelated traits in both diploid parents and allotetraploids: Morphological traits (such as leaf area and perimeter) anatomic traits (including ab- and ad- axial epidermis) and aspects of physiology. In general, there were more correlations between structural and functional traits for allotetraploid hybrids than diploid parents. Parents and hybrids did not have any significant structure-function correlations in common. Of particular note, there were no significant correlations between morphological structure and physiological function in the diploid parents. Increased phenotypic integration in the allotetraploid hybrids may be due, in part, to increased trait ranges or simply different structure-function relationships. Conclusions Genomic and chromosomal instability in early generation allotetraploids may allow Brassica species to explore new trait space and potentially reach higher adaptive peaks than their progenitor species could, despite temporary fitness costs associated with unstable genomes. The trait correlations that disappear after hybridization as well as the novel trait correlations observed in allotetraploid hybrids may represent relatively evolutionarily labile associations and therefore could be ideal targets for artificial selection and crop improvement. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0957-3) contains supplementary material, which is available to authorized users.