seckel syndrome seckel syndrome 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 an extremely rare congenital nanosomic disorder. inheritance is autosomal recessive. it is characterized by intrauterine growth restriction and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with down-slanting palpebral fissures, receding mandible and intellectual disability. seckel syndromeother namesharper's syndromeboy with seckel syndrome (left)specialtymedical geneticscausesdefects of genes on chromosome 3 and 18. a mouse model has been developed. this mouse model is characterized by a severe deficiency of atr protein. these mice have high levels of replicative stress and dna damage. adult seckel mice display accelerated ageing. these findings are consistent with the dna damage theory of aging. symptoms and signs symptoms include: intellectual disability (more than half of the patients have an iq below 50) microcephaly sometimes pancytopenia (low blood counts) cryptorchidism in males low birth weight dislocations of pelvis and elbow unusually large eyes blindness or visual impairment large, low-set ears small chin due to receded lower jaw genetics it is believed 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 (atr) which maps to chromosome 3q22.1-q24. this gene is central in the cell's dna damage response and repair mechanism. types include: type omim gene locus sckl1 210600 atr 3q22-q24 sckl2 606744 ? 18p11-q11 sckl3 608664 ? 14q sckl4 613676 cenpj 13q12 diagnosis history the syndrome was named after german-american physician helmut paul george seckel (1900–1960). the synonym harper's syndrome was named after rita g. harper.