There is no definate answer to what problems a child with 1p36 deletion syndrome will have. However it has been found that children with 1p36 deletion syndrome may have problems in the following areas:

Most young children with 1p36 deletion syndrome have delayed development. They sit up, walk and talk later than typical children. Speech is severely affected with many patients learning only a few words. The degree of mental retardation and ability to acquire complex speech is somewhat dependent on deletion size. Reports of a milder learning disability in children with smaller deletions have suggested that there may be a correlation between deletion size and mental ability, however this has not been proven yet and it requires further investigation and research.

Many children with 1p36 deletion syndrome have behavior problems. Some of these include temper outbursts, banging or throwing objects, striking people, screaming episodes, and
self-injurious behaviour (wrist biting, head striking/banging. Autistic behaviour has also
been noted in some children.

Many children with 1p36 deletion syndrome have oropharyngeal dysphasia which is characterized by difficulty in initiating a swallow.  Some of the other feeding problems include poor sucking and swallowing, reflux, and vomiting in infancy.

Cranial imaging (imaging of the brain area) has documented cerebral atrophy which is a loss of neurons in the brain and the connections between them. Also documented were problems with the ventricles in the brain such as ventricular asymmetry and ventricular enlargement. Hydrocephalus has also been noted in children with 1p36 deletion syndrome. This is basically too much fluid within the brain. Hyperreflexia, which is defined as overactive or overresponsive reflexes in the body, was also found to be common. Many children also have epilepsy which is a disorder of the brain that results in recurrent, unprovoked seizures.

Microcephaly is a nerological disorder in which the circumference of the head is smaller than average for the person's age and gender. Most children with microcephaly also have a small brain and mental retardation. Some of the most common symptoms of microcephaly are having an apperance of a small head, seizures, poor feeding, high pitched cry, mental retardation, developmental delay, and increased movement of arms and legs. The diagnosis of microcephaly may be made at birth or later in infancy.

Visual abnormalities in children with 1p36 have been wide-ranging, including:

• Strabismus: A condition in which the two eyes do not point in the same direction when the patient is looking at a distant object.
• Sixth Nerve Palsy: Double vision
• Refractive Errors: Refractive errors include nearsightedness, farsightedness, astigmatism (a warping of the curvature of the cornea) and presbyopia (the inability to maintain a clear image or focus as objects are moved closer). These disorders of the eye can be corrected with glasses or contacts.
• Hypermetropia: Normal eye condition where the eye is too small and eyes have to over focus to see clearly; also called longsightedness.
• Cataracts: A cataract is an opacity or cloudiness in the natural lens of the eye.
• Nystagmus: The condition characterized by the repetitive oscillations (vibration) of the eyes. Parents of children with nystagmus often refert to this as "jerking" "or "jiggling" eyes.
• Lacrimal defects: The lacrimal glands in the eye secrete tears.
• Visual inattentiveness: Defined as an absence of attentive visual behavior such as fixation and following  movements.

Children with 1p36 deletion syndrome are all unique individuals, but do have some common distinct facial features such as:

• Large anterior fontanelle/Frontal bossing: The anterior fontanelle is the "soft spot" towards the front of the top of an infant's head between the growing skull bones. Frontal bossing simply means a prominent forehead.
• Small and pointed chin
• Flat nose and/or nasal bridge
• Clinodactyly and/or short fifth finger: Clinodactyly is the curving of the fifth finger (the little finger) toward the fourth finger.
• Low-set, small ears/Ear asymmetry: Ears are abnormally low set on the head and may be small. They may be asymmetrical meaning that they may not be the same shape or size, or not lined up.
• Small head: Also known as microcephaly
• Deep set eyes
• Thickened ear helices: Ear helices are the outer rings of cartilage of the ears.
• Short, narrow and slanting palpebral fissures: Palperbral fissures are the gaps between the upper and lower eyelids, or the opening of the eyes.
• Midface Hypoplasia: This is where the middle of the face is underdeveloped, leading to a concave-looking face. The bridge of the nose looks sunken in and the eyes are set widely apart and often protrude out of the sockets.
• Small mouth with down-turned corners
• Orofacial clefting: This is a relatively common birth defect in which the fetus develops with deformities of the upper lip, gum, and roof of the mouth. Children with 1p36 have been noted to have orofacial clefting involving the lip and/or palate or uvula (a little piece of flesh hanging down inside the mouth at the back of the palate).

There are many growth abnormalities associated with 1p36 deletion syndrome. One problem in children with 1p36 is having delayed growth or difficulty in gaining weight. Even though some of the children may eat well, they still may not grow normally. Some children may develop hyperphagia, which is overeating, and may become obese. These children clinically resemble children with Prader-Willi syndrome. Developmental delay has also been severe in the patients with the Prader-Willi like characteristics.

Hypotonia is decreased or low muscle tone. This may explain the delayed motor skills in children with 1p36.

Hypothyroidism is too little of the thyroid hormone. Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold. Around one third of children with the syndrome have this low thyroid function, which is also called underactive thyroid, and leads to slow metabolism and fatigue.

There are a few heart defects that affect children with 1p36 deletion syndrome, and they are as follows:

• Infantile Dilated Cardiomyopathy:  Dilated Cardiomyopathy (DCM) is a disease of the heart muscle that causes the heart to become enlarged, and to pump less strongly. This causes fluid to build up in the lungs, which therefore become congested, and results in a feeling of breathlessness. None of the children with DCM, who also have 1p36 deletion syndrome, worsened over time, however some have to continue taking medication.
• Patent Ductus Arteriosus: This is the most common structural heart defect in children with 1p36. This is a condition in which the connecting blood vessel between the pulmonary artery and the aorta in fetal circulation stays open in the newborn. The defect often corrects itself within several months of birth, but may require infusion of chemicals, the placement of "plugs" via catheters, or surgical closure.
• Tetralogy of Fallot: Tetralogy of Fallot is a Ventricular Septal Defect, which is a hole between the two ventricles and Pulmonary Stenosis, which is a narrowing between the right ventricle and the artery carrying blood to the lungs. These defects can cause less blood flow to the lungs, the mixing of oxygen-rich and oxygen-poor blood inside the heart, and low levels of oxygen in the blood. When oxygen levels are low, the baby's skin, fingertips, or lips have a bluish tint. This condition is called cyanosis. An infant with cyanosis is sometimes called a "blue baby."

Chromosome 1p36 alterations, mostly deletions, have been reported to occur in various neoplasms. A neoplasm is a new growth or tumor which may be benign (not cancerous) or malignant (cancerous). The 1p36 region contains a number of tumor-suppressor genes, which are genes that act to prevent cell growth. The deletion of one or more of these genes can cause malignancy (cancer). Some of the neoplams involved in the 1p36 are are neuroblastoma, prostate cancer, lung cancer, malignant melanoma, hepatoma, cervical carcinoma, breast cancer, colorectal adenocarcinoma, ovarian cancer,  and non-Hodgkin lymphoma. This is not to say that the children with 1p36 deletion syndrome will get these cancers, as this is just a theory.

Genital hypoplasia is the underdevelopment of the genital areas. Some of the genital problems in children with 1p36 are:

• Cryptorchidism: This is the failure of one or both of the testicles to descend into the scrotum.
• Shaw Scrotum: A condition in which the scrotum tends to surround the penis.
• Small Genitalia
• Dilation of the renal(kidney) collecting system: The collecting system is the structure that collects urine directly from the kidney tissue and routes it by way of the ureter to the bladder. This dilation is called hydronephrosis and is also known as "swelling of the kidney". Structural renal (kidney) abnormalities are rare in both sexes.

Sensorineural hearing loss which is a type of hearing impairment caused by damage that occurs to the inner ear (cochlea) and/or nerve of hearing, or conductive hearing loss, which is  a hearing loss associated with the functioning of the outer or middle ear is common in children with 1p36 deletion syndrome. It ranges from mild loss at high frequencies,  to severe loss at all frequencies.

Puberty, in children with 1p36 deletion syndrome, has been reported to be both early and delayed.

Only a few spine deformities have been seen in children with 1p36. The deformities found are:

• Kyphoscoliosis: Spinal deformity combining sideways curvature and hunching forward of the upper part of the spine.
• Thoracic Kyphosis: Also called postural "round back". This was found secondary to hypotonia in some children with 1p36.