(See also Overview of Chromosome Disorders Overview of Chromosome and Gene Disorders Chromosomes are structures within cells that contain a person's genes. A gene is a segment of deoxyribonucleic acid (DNA) and contains the code for a specific protein that functions in one or... read more .)
In Wolf-Hirschhorn syndrome, part of chromosome 4 is missing.
Children who survive into their 20s typically have severe disabilities.
Symptoms of Wolf-Hirschhorn syndrome often include profound intellectual disability Intellectual Disability Intellectual disability is significantly below average intellectual functioning present from birth or early infancy, causing limitations in the ability to conduct normal activities of daily... read more . Children may also have epilepsy Seizures in Children Seizures are a periodic disturbance of the brain’s electrical activity, resulting in some degree of temporary brain dysfunction. When older infants or young children have seizures, they often... read more , a broad or beaked nose, scalp defects, drooping upper eyelids (ptosis) and gaps or fissures (colobomas) of the iris, cleft palate Cleft Lip and Cleft Palate The most common birth defects of the skull and face are cleft lip and cleft palate, affecting about 2 of every 1,000 babies. Cleft lip is a separation of the upper lip, usually just below the... read more , and delayed bone development. Boys may have undescended testes Undescended Testes and Retractile Testes Undescended testes (cryptorchidism) are testes that remain in the abdomen or the groin instead of descending into the scrotum. Retractile testes (hypermobile testes) have descended into the... read more (cryptorchidism) and a misplaced opening of the urethra (hypospadias Hypospadias Defects of the genitals can involve the penis, scrotum, or testes (testicles) in boys and the vagina and labia in girls. Sometimes the genitals are ambiguous, that is, not clearly female or... read more ). Some children have an immune deficiency, which means their body is less able to fight off infections. Many affected children die during infancy.