# Coexistence of pulmonary arterial hypertension and straight back syndrome in a patient with a novel BMPR2 variant affecting cytoplasmic tail domain

## TL;DR

A 30-year-old woman with a new BMPR2 gene variant was found to have both pulmonary arterial hypertension and straight back syndrome, a first in medical literature.

## Contribution

This is the first report linking a novel BMPR2 variant with straight back syndrome in heritable pulmonary arterial hypertension.

## Key findings

- A novel germline BMPR2 frameshift variant (c.2423_2424delGT) was identified in a patient with pulmonary arterial hypertension.
- The patient also exhibited straight back syndrome, a previously unreported co-occurrence with heritable pulmonary arterial hypertension.
- The variant affects the cytoplasmic tail domain of BMPR2, potentially contributing to variable disease penetrance.

## Abstract

Pathologic variants in the bone morphogenetic protein receptor-2 (BMPR2) gene cause a pulmonary arterial hypertension phenotype in an autosomal-dominant pattern with incomplete penetrance. Straight back syndrome is one of the causes of pseudo-heart diseases. To date, no cases of idiopathic or heritable pulmonary arterial hypertension with straight back syndrome have been reported.

A 30-year-old female was diagnosed with pulmonary arterial hypertension by right heart catheterization. Computed tomography revealed a decreased anteroposterior thoracic space with heart compression, indicating a straight back syndrome. Genetic analysis by whole exome sequencing identified a novel c.2423_2424delGT (p.G808Gfs*4) germline frameshift variant within BMPR2 affecting the cytoplasmic tail domain.

This is the first report of different straight back characteristics in heritable pulmonary arterial hypertension with a novel germline BMPR2 variant. This finding may provide a new perspective on the variable penetrance of the pulmonary arterial hypertension phenotype.

The online version contains supplementary material available at 10.1186/s40001-024-01810-x.