Monosomy 18p Q93.5

Monosomy 18p is a chromosomal disorder with complete or partial deletion of the short arm of a chromosome 18.

The prevalence among live births is 1-9 / 100 000. The most common form is one with very moderate and non-specific dysmorphia.

In 2/3 of the cases, the 18p-minus syndrome is due to a merely terminal new deletion. In the remaining cases there are the following possibilities: (i) de novo translocation with loss of 18p, (ii) mis-segregation of a parental translocation or inversion, or (iii) a ring chromosome 18. Parental transmission of the 18p-minus syndrome has been described.

Newborn Time

Cliknsich syndrome is characterized by: short stature, round face, short philtrum, lid ptosis and large and protruding ears. The intelligence is slightly to moderately reduced. Only about 10-15% of patients, have severe brain and facial malformations.

Cytogenetic examination

In young children, the syndrome may resemble either Turner syndrome or trisomy 21. These must be ruled out by genetic testing.

There is no specific treatment, but speech therapy and early educational programs favorably affect children's behavior and performance.

Life expectancy is not significantly limited.

Described (Zoubulis 1994) was a triad of keratosis pilaris, ulerythema ophryogenes, and monosomy 18p (Liakou AI et al. 2014) .

1. Crosiers D et al (2018) Spectrum of Movement Disorders in 18p Deletion Syndrome. Mov Disord Clin Pract 6:70-73.
2. Liakou AI et al (2014) Trias of keratosis pilaris, ulerythema ophryogenes and 18p monosomy: Zouboulis syndrome. J Dermatol 41:371-376.