Seckel syndrome

The Seckel syndrome or microcephalic primordial dwarfism (also known as bird-headed dwarfism, Harper's syndrome, Virchow-Seckel dwarfism, and Bird-headed dwarf of Seckel )  is a congenital nanosomic disorder.

Inheritance is autosomal recessive.

It is characterized by intrauterine growth retardation and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with an antimongoloid slant, receding mandible and mental retardation.

A mouse model has been developed.

Genetics
It is supposed to be caused by defects of genes on chromosome 3 and 18. One form of Seckel syndrome can be caused by mutation in the gene encoding the ataxia telangiectasia and Rad3 related protein which maps to chromosome 3q22.1-q24. This gene is central in the cell's DNA damage response and repair mechanism.

Types include:

History
The syndrome was named after Helmut Paul George Seckel (American physician, 1900–1960). Harper's syndrome is named after Rita G. Harper.

Symptoms
Symptoms include:
 * mental retardation (more than half of the patients have an IQ below 50)
 * microcephaly
 * sometimes pancytopenia
 * cryptorchidism
 * low birth weight
 * dislocations of pelvis and elbow
 * unusually large eyes
 * low ears
 * small chin