Potocki–Shaffer syndrome (PSS), also known as DEFECT11 syndrome or chromosome 11p11.2 deletion syndrome, is a rare contiguous gene syndrome that results from the

microdeletion In genetics, a deletion (also called gene deletion, deficiency, or Deletion anomaly, deletion mutation) (sign: delta (letter), Δ) is a mutation (a genetic aberration) in which a part of a chromosome or a sequence of DNA is left out during DNA rep ...

of section 11.2 on the short arm of

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

11 (11p11.2). The syndrome has its name from Dr. Lorraine (Lori) Potocki and Dr. Lisa Shaffer who discovered the deletion on the 11th chromosome and studied the impacts. The deletion of this combination of genes results in several distinctive

congenital A birth defect is an abnormal condition that is present at childbirth, birth, regardless of its cause. Birth defects may result in disability, disabilities that may be physical disability, physical, intellectual disability, intellectual, or dev ...

features, occasional defects in the heart, kidneys, and urinary tract. The disorder is associated with an enlarged

parietal foramina A parietal foramen is an opening in the skull for the parietal emissary vein, which drains into the superior sagittal sinus. Occasionally, a small branch of the occipital artery can also pass through it. Each foramen is located at the back part of ...

which can cause openings in the two bones that form the top and sides of the skull. These abnormal openings form extra "soft spots" on the head, in addition to the two that newborns normally have, and unlike the usual newborn soft spots, the enlarged parietal foramina remain open throughout life. Other signs can include multiple mostly noncancerous

benign Malignancy () is the tendency of a medical condition to become progressively worse; the term is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous benign tumor, ''benign'' tumor in that a malig ...

bone tumours called

osteochondroma Osteochondroma is the most common benign tumor of bone. The tumors take the form of cartilage-capped bony projections or outgrowth on the surface of bones ( exostoses). It is characterized as a type of overgrowth that can occur in any bone where ...

s (

exostosis An exostosis, also known as a osteochondroma, is a benign chondrogenic lesions derived from aberrant cartilage from the perichondral ring. Exostoses can cause chronic pain ranging from mild to moderate, but rarely severe, depending on the shape, s ...

developmental delay The term developmental delay can refer to: *Global developmental delay, an umbrella term used when children are significantly delayed in two or more areas of development *Specific developmental disorder, a classification of disorders characterize ...

, vision disorders and craniofacial abnormalities. It is classified as a

rare disease A rare disease is any disease that affects a small percentage of the population. In some parts of the world, the term orphan disease describes a rare disease whose rarity results in little or no funding or research for treatments, without financi ...

Signs and symptoms

The signs and symptoms of Potocki–Shaffer syndrome vary widely. In addition to multiple osteochondromas and enlarged parietal foramina, affected individuals often have

intellectual disability Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental ...

and delayed development of speech,

motor skills A motor skill is a function that involves specific movements of the body's muscles to perform a certain task. These tasks could include walking, running, or riding a bike. In order to perform this skill, the body's nervous system, muscles, and b ...

(such as sitting and walking), and

social skills A social skill is any competence facilitating interaction and communication with others where social rules and relations are created, communicated, and changed in verbal and nonverbal ways. The process of learning these skills is called socia ...

. Many people with this condition have distinctive facial features, which can include a wide, short skull (

brachycephaly Brachycephaly (derived from the Ancient Greek '' βραχύς'', 'short' and '' κεφαλή'', 'head') is the shape of a skull shorter than average in its species. It is perceived as a cosmetically desirable trait in some domesticated dog and ...

); a prominent forehead; a narrow bridge of the nose; a shortened distance between the nose and upper lip (a short

philtrum The philtrum (, from Ancient Greek , lit. 'love charm') or medial cleft is a vertical indentation in the middle area of the upper lip, common to therian mammals, extending in humans from the nasal septum to the tubercle of the upper lip. Toget ...

); and a downturned mouth. Less commonly, Potocki–Shaffer syndrome causes

vision problems Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficul ...

, additional skeletal abnormalities, and defects in the

heart The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

s, and

urinary tract The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressu ...

Genetics

Potocki–Shaffer syndrome follows an autosomal dominant inheritance pattern, which means a deletion of genetic material from one copy of

chromosome 11 Chromosome 11 is one of the 23 pairs of chromosomes in humans. Humans normally have two copies of this chromosome. Chromosome 11 spans about 135 million base pairs (the building material of DNA) and represents between 4 and 4.5 percent of the tota ...

is sufficient to cause the disorder. In some cases, an affected person inherits the chromosome with a deleted segment from an affected

parent A parent is either the progenitor of a child or, in humans, it can refer to a caregiver or legal guardian, generally called an adoptive parent or step-parent. Parents who are progenitors are First-degree relative, first-degree relatives and have ...

. More commonly, the condition results from a deletion that occurs during the formation of

reproductive cells A gamete ( ) is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. The name gamete was introduced by the Ger ...

(eggs and

sperm Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...

) in a parent or in early

fetal development Prenatal development () involves the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal deve ...

. These cases occur in people with no history of the disorder in their family.

Diagnosis

Potocki–Shaffer syndrome can be detected through array comparative genomic hybridization (aCGH).

Management

Some symptoms can be managed with drug therapy,

surgery Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

and rehabilitation, genetic counselling, and

palliative care Palliative care (from Latin root "to cloak") is an interdisciplinary medical care-giving approach aimed at optimizing quality of life and mitigating or reducing suffering among people with serious, complex, and often terminal illnesses. Man ...

References

External links