Čes-slov Pediat 2025, 80(90):35-38 | DOI: 10.55095/CSPediatrie2025/054

Two generations of a family with a variant growth hormone molecule

Barbora Jírová^*, Lukáš Kavčiak^*, Petra Dušátková, Lukáš Plachý^#, Jan Lebl^#

Pediatrická klinika, 2. lékařská fakulta, Univerzita Karlova a Fakultní nemocnice v Motole, Praha

Growth hormone deficiency (GHD) results in serious short stature. In individual families, this condition may be caused by pathogenic gene variants. We present two half-siblings sharing the same father who were subsequently, over several years, diagnosed with GHD using stimulation tests. Genetic investigation confirmed a

pathogenic missense GH1 gene variant c.626G>A (p.Arg209His) with autosomal dominant transmission. GH1 gene encodes the human growth hormone molecule. With this variant, GH bioactivity remains unchanged but growth hormone release from pituitary cell secretory granules is

compromised and delayed. Growth hormone stimulation tests may show low, borderline, but even normal results. Both the girl and the boy started GH treatment with heights of -2.71 SD and -3.29 SD. The girl had normal puberty and completed growth with final height 161.2 cm (-0.95 SD). The boy, currently aged 8 years, is still on therapy and has reached height -0.73 SD. The gene variant was confirmed

in children's father who has height 165.4 cm (-2.13 SD). He was never treated in childhood and is now a candidate for adult growth hormone replacement for metabolic indication. Genetic testing may be helpful to diagnose GHD, especially when stimulation tests end inconclusive.

Keywords: growth hormone, growth hormone deficiency, GH1 gene, stimulation tests

Accepted: September 24, 2025; Published: September 1, 2025  Show citation