Features include always present findings: Decreased calvarial ossification, Ulnar bowing, Hypoplastic acetabulae, and Mild bone density loss (osteopenia) and others; and common findings: Femoral bowing, Enlarged liver (hepatomegaly), Relative macrocephaly, and Short 1st metacarpal and others.

LAMA5 encodes laminin subunit alpha 5 (3,695 aa). Binding to cells via a high affinity receptor, laminin is thought to mediate the attachment, migration and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components. Highest expression in Colon Sigmoid (175.2 TPM) and Artery Tibial (171.8 TPM).

Bent bone dysplasia syndrome 2 is associated with mutations in the LAMA5 gene on chromosome 20.

The LAMA5 protein participates in Expression of IL4, IL13-upregulated extracellular proteins pathway.

LAMA5 is classified as a druggable target (Druggable Genome category) with score 1.4.

Genetic testing for LAMA5 is available. Testing is considered confirmatory for diagnosis.

Phenotype severity distribution: 13 always present features, 18 common features.

No clinical trials have been registered for bent bone dysplasia syndrome 2.

2 publications have been identified in PubMed for bent bone dysplasia syndrome 2. Research spans Review / Meta-Analysis (50%) and Case Report / Case Series (50%).

Recent Publications

• Singh S (2025). [PMID: 39506047](https://pubmed.ncbi.nlm.nih.gov/39506047/). *Eur J Hum Genet*. [Case Report / Case Series]

• Begam MA (2025). [PMID: 40521311](https://pubmed.ncbi.nlm.nih.gov/40521311/). *J Med Ultrasound*. [Review / Meta-Analysis]