Chromosome 9p syndrome Q93.5

Chromosome 9p syndrome, also known as Alfi syndrome, is a rare dysmorphia syndrome based on a very rare, sporadic chromosomal defect that causes severe mental, physical and somatic impairment.

About 350 cases have been reported worldwide; an incidence of 1:50,000 newborns is assumed.

Sporadic defect on chromosome 9, in which a small part of the short chromosome arm (segment 9p22.2-p23) is missing, so that important genes for the development of the child are missing

Symptoms similar to Down's syndrome are present with trigonobrachycephaly, round and flat face, high flat and narrow forehead, synophrysis, bushy eyebrows, almond-shaped eyes, hypertelorism, pseudoexophthalmos, protruding lower lip, flat and broader nasal root, a nose with forward facing openings, dysplastic auricles, a short neck, short fingers, genital hypoplasia, widely spaced nipples, heart defects and muscle weakness, and severe psychomotor retardation (Huret JL et al. 1988). Neurologically, dysmorphia of the corpus callosum as well as hypoplasia of the substantia alba can be detected (Spazzapan P et al. 2016).

Some affected children are often very open and friendly, also towards strangers. Others, however, behave autistically (Spazzapan P et al. 2016).

Depending on the type and severity of the symptoms, different prognoses can be expected. Some children with mild cognitive impairment and minor organ damage can lead an almost normal life with normal life expectancy. Children in whom the syndrome is more pronounced may have a shorter life expectancy and are dependent on continuous care by their parents.

1. Güneş S et al. (2017) Coexistence of 9p Deletion Syndrome and Autism Spectrum Disorder. J Autism Dev Disord 47:520-521.
2. Huret JL et al. (1988) Eleven new cases of del (9p) and features from 80 cases. J Med Genet 25:741-749.
3. Ioan D et al. (1990) A 22-year old female with the 9p deletion syndrome. Endocrinology 28:37-39.
4. Spazzapan P et al (2016) Clinical and neuroradiological features of the 9p deletion syndrome. Childs nerve syst 32:327-335.