1p36 deletion syndrome, or monosomy 1p36, is a chromosomal abnormality characterised most commonly by a deletion in the distal segment of the short arm of chromosome one 1.
The 1p36 deletion syndrome is present in approximately 1 in 5000 live births. It is the most common terminal deletion syndrome 2.
There is a large spectrum of variability in the clinical presentation of monosomy 1p36. Some of the neurodevelopmental and physical abnormalities that may be present in 1p36 deletion syndrome are featured below 1,3:
- growth retardation (ante- and postnatal), however obesity can also be present in subtypes that feature hyperphagia (similar to Prader-Willi syndrome)
- dysmorphic features
- neurological abnormalities
- cardiac malformations and disorders
Findings on antenatal ultrasound such as ventriculomegaly, cardiac malformations and midface hypoplasia, sometimes associated with intrauterine growth restriction (IUGR), as well as various other anomalies, should prompt suspicion for 1p36 deletion syndrome 5.
- 1. Watanabe M, Hayabuchi Y, Ono A, Naruto T, Horikawa H, Kohmoto T, Masuda K, Nakagawa R, Ito H, Kagami S, Imoto I. Detection of 1p36 deletion by clinical exome-first diagnostic approach. Human genome variation. 3: 16006. doi:10.1038/hgv.2016.6 - Pubmed
- 2. Valerie K Jordan, Hitsha P Zaveri, Daryl A Scott. 1p36 deletion syndrome: an update. The Application of Clinical Genetics. 8: 189. doi:10.2147/TACG.S65698
- 3. Anne Slavotinek, Lisa G Shaffer, Stuart K Shapira. Monosomy 1p36. Journal of Medical Genetics. 36 (9): 657. doi:10.1136/jmg.36.9.657 - Pubmed
- 4. Shiba N, Daza RA, Shaffer LG, Barkovich AJ, Dobyns WB, Hevner RF. Neuropathology of brain and spinal malformations in a case of monosomy 1p36. Acta neuropathologica communications. 1: 45. doi:10.1186/2051-5960-1-45 - Pubmed
- 5. Chen CP, Chen M, Su YN, Hsu CY, Tsai FJ, Chern SR, Wu PC, Lee CC, Wang W. Chromosome 1p36 deletion syndrome: prenatal diagnosis, molecular cytogenetic characterization and fetal ultrasound findings. Taiwanese journal of obstetrics & gynecology. 49 (4): 473-80. doi:10.1016/S1028-4559(10)60100-3 - Pubmed