Most cited article - PubMed ID 24581273
Anophthalmia, hearing loss, abnormal pituitary development and response to growth hormone therapy in three children with microdeletions of 14q22q23
Because the causes of combined pituitary hormone deficiency (CPHD) are complex, the etiology of congenital CPHD remains unknown in most cases. The aim of the study was to identify the genetic etiology of CPHD in a well-defined single-center cohort. In total, 34 children (12 girls) with congenital CPHD (growth hormone (GH) deficiency and impaired secretion of at least one other pituitary hormone) treated with GH in our center were enrolled in the study. Their median age was 11.2 years, pre-treatment height was -3.2 s.d., and maximal stimulated GH was 1.4 ug/L. Of them, 30 had central adrenal insufficiency, 27 had central hypothyroidism, ten had hypogonadotropic hypogonadism, and three had central diabetes insipidus. Twenty-six children had a midline defect on MRI. Children with clinical suspicion of a specific genetic disorder underwent genetic examination of the gene(s) of interest via Sanger sequencing or array comparative genomic hybridization. Children without a detected causal variant after the first-tier testing or with no suspicion of a specific genetic disorder were subsequently examined using next-generation sequencing growth panel. Variants were evaluated by the American College of Medical Genetics standards. Genetic etiology was confirmed in 7/34 (21%) children. Chromosomal aberrations were found in one child (14q microdeletion involving the OTX2 gene). The remaining 6 children had causative genetic variants in the GLI2, PROP1, POU1F1, TBX3, PMM2, and GNAO1 genes, respectively. We elucidated the cause of CPHD in a fifth of the patients. Moreover, our study supports the PMM2 gene as a candidate gene for CPHD and suggests pathogenic variants in the GNAO1 gene as a potential novel genetic cause of CPHD.
- Keywords
- combined pituitary hormone deficiency, genetics of short stature, growth hormone deficiency, next-generation sequencing, short stature,
- Publication type
- Journal Article MeSH
BACKGROUND: Interstitial microdeletion 14q22q23 is a rare chromosomal syndrome associated with variable defects: microphthalmia/anophthalmia, pituitary anomalies, polydactyly/syndactyly of hands and feet, micrognathia/retrognathia. The reports of the microdeletion 14q22q23 detected in the prenatal stages are limited and the range of clinical features reveals a quite high variability. CASE PRESENTATION: We report a detection of the microdeletion 14q22.1q23.1 spanning 7,7 Mb and involving the genes BMP4 and OTX2 in the foetus by multiplex ligation-dependent probe amplification (MLPA) and verified by microarray subsequently. The pregnancy was referred to the genetic counselling for abnormal facial profile observed in the first trimester ultrasound scan and micrognathia (suspicion of Pierre Robin sequence), hypoplasia nasal bone and polydactyly in the second trimester ultrasound scan. The pregnancy was terminated on request of the parents. CONCLUSION: An abnormal facial profile detected on prenatal scan can provide a clue to the presence of rare chromosomal abnormalities in the first trimester of pregnancy despite the normal result of the first trimester screening test. The patients should be provided with genetic counselling. Usage of quick and sensitive methods (MLPA, microarray) is preferable for discovering a causal aberration because some of the CNVs cannot be detected with conventional karyotyping in these cases. To the best of our knowledge, this is the earliest detection of this microdeletion (occurred de novo), the first case detected by MLPA and confirmed by microarray. Literature review of the genotype-phenotype correlation in similar reports leads us to the conclusion that dosage imbalance of the chromosomal segment 14q22q23 (especially haploinsuffiency of the genes BMP4 and OTX2) contributes significantly to orofacial abnormalities. Association of the region with the Pierre Robin sequence appears to be plausible.
- Keywords
- First trimester ultrasound, Microdeletion 14q22q23, Micrognathia, Pierre Robin sequence,
- Publication type
- Journal Article MeSH
- Case Reports MeSH