Diphallia
Encyclopedia
Diphallia, penile duplication (PD), diphallic terata, or diphallasparatus, is a medical condition in which a male infant is born with two penis
es. This is an extremely rare disorder
with only approximately 100 cases of diphallia recorded since the first, reported by Johannes Jacob Wecker
in 1609 . Its occurrence is one in five and a half million men in the United States
.
When diphallia is present, it is usually accompanied by other congenital anomalies such as renal
, vertebral, hindgut
or anorectal
duplication. There is also a higher risk of spina bifida
. Infants born with PD and its related conditions have a higher death rate from various infections associated with their more complex renal or colorectal systems.
It is thought diphallia occurs in the fetus
between the 23rd and 25th days of gestation
when an injury, chemical stress, or malfunctioning homeobox
genes hamper proper function of the caudal cell mass
of the fetal mesoderm as the urogenital sinus
separates from the genital tubercle
and rectum
to form the penis.
This rare condition has been documented in pig
s and other mammal
s.
Diphallia is a medical condition and should not be confused with genital bisection
, which is an elective procedure which involves the splitting of the penis.
Penis
The penis is a biological feature of male animals including both vertebrates and invertebrates...
es. This is an extremely rare disorder
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...
with only approximately 100 cases of diphallia recorded since the first, reported by Johannes Jacob Wecker
Johannes Jacob Wecker
Johannes Jacob Wecker was a Swiss physician. Little is known about his life. He published Antidotarum generale, a work about alchemy. His work is known for the elaborate bibliography on chemistry-alchemy...
in 1609 . Its occurrence is one in five and a half million men in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
When diphallia is present, it is usually accompanied by other congenital anomalies such as renal
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
, vertebral, hindgut
Hindgut
The hindgut is the posterior part of the alimentary canal. In mammals, it includes the distal third of the transverse colon and the splenic flexure, the descending colon, sigmoid colon and rectum.-Blood flow:...
or anorectal
Anorectal
Not to be confused with anorexia.Anorectal anomalies are medical problems affecting the structure of the anus and rectum. A person with an anorectal problem would have some sort of deformative feature of the anus or rectum, collectively known as an anorectal malformation.Examples of anorectal...
duplication. There is also a higher risk of spina bifida
Spina bifida
Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...
. Infants born with PD and its related conditions have a higher death rate from various infections associated with their more complex renal or colorectal systems.
It is thought diphallia occurs in the fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
between the 23rd and 25th days of gestation
Gestation
Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during pregnancy can have one or more gestations at the same time ....
when an injury, chemical stress, or malfunctioning homeobox
Homeobox
A homeobox is a DNA sequence found within genes that are involved in the regulation of patterns of anatomical development in animals, fungi and plants.- Discovery :...
genes hamper proper function of the caudal cell mass
Caudal cell mass
In humans and other mammals, the caudal cell mass is the aggregate of undifferentiated cells at the caudal end on the spine, sometimes called the tail bud in humans....
of the fetal mesoderm as the urogenital sinus
Urogenital sinus
The definitive urogenital sinus is a part of the human body only present in the development of the urinary and reproductive organs...
separates from the genital tubercle
Genital tubercle
A phallic tubercle or genital tubercle is a body of tissue present in the development of the urinary and reproductive organs. It forms in the ventral, caudal region of mammalian embryos of both sexes, and eventually develops into a phallus...
and rectum
Rectum
The rectum is the final straight portion of the large intestine in some mammals, and the gut in others, terminating in the anus. The human rectum is about 12 cm long...
to form the penis.
Characteristics
- Those in possession of a diphallus tend to be sterileInfertilityInfertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...
, due to either congenital defectsCongenital disorderA congenital disorder, or congenital disease, is a condition existing at birth and often before birth, or that develops during the first month of life , regardless of causation...
or difficulties in application. - UrineUrineUrine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
may be passed by both penises, by only one, or through some other apertureApertureIn optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
in the perineumPerineumIn human anatomy, the perineum is a region of the body including the perineal body and surrounding structures...
. - A range of duplication types have been seen, ranging from organsOrgan (anatomy)In biology, an organ is a collection of tissues joined in structural unit to serve a common function. Usually there is a main tissue and sporadic tissues . The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are...
that fissureFissureIn anatomy, a fissure is a groove, natural division, deep furrow, elongated cleft, or tear in various parts of the body.-Brain:...
into two, to the presence of two distinct penises positioned at some distance from each other. - Most diphalluses lie side by side and are of equal size, but they can be seated atop one another, with one distinctly larger than the other.
This rare condition has been documented in pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s and other mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s.
Diphallia is a medical condition and should not be confused with genital bisection
Genital bisection
Genital bisection in males involves the splitting of the penis . This still allows for erection, though often the two halves curve into each other, making insertion more difficult....
, which is an elective procedure which involves the splitting of the penis.