Cleft lip and cleft palate are congenital deformities that result in the palate or the lip or both not coming together to fuse in the middle during the fetal formation of facial structures. This occurs early in gestation, as the structures begin...
Alzheimer's disease causes severe disruption in critical thinking, memory, judgment and social skills. The dementia of Alzheimer's occurs along with distinctive changes in the brain, including abnormal protein deposits of plaques and tangles. The...
Huntington's disease is an inherited disorder characterized by the destruction of nerve cells in specific areas of the brain. Symptoms present in adulthood with the onset most frequently occurring during the third or fourth decade of life. Early...
There are about 35,000 genes in the nucleus of human body cells. These genes are packaged into 23 pairs of chromosomes, numbered 1 through 22, with the 23rd pair being the sex chromosomes (X and Y). Each of the genes has a specific role in the...
The human hairless (HR) gene is found on chromosome 8 and has been implicated in several hereditary diseases that result in permanent hair loss. The HR protein normally acts as a genetic manager, controlling the expression of other genes....
Crohn's disease causes severe inflammation of the digestive system, with potentially serious complications. Although scientists know that some people inherit Crohn's disease, no single gene causes the disease. Crohn's disease is complex, meaning...
Almost all human disease has a genetic basis, even those associated with lifestyle choices such as obesity, heart disease and alcoholism. So why do genetic diseases occur in some people, but not in others? The answer lies in the human genome. ...
If you're pregnant, prenatal testing may seem like a positive thing, a way to check your baby's health and find out whether you're having a boy or girl. While 97 percent of all prenatal tests deliver good news, according to the University of...
Every pregnancy has a risk that the fetus carries a serious genetic defect. Doctors have developed ways to calculate the risk of a serious chromosomal abnormality fairly early in pregnancy. In the first trimester, nuchal translucency, or the...
About 50 percent of women over age 40 have fertility problems, the March of Dimes states. But even if a woman over 40 does get pregnant, she has a higher risk of complications during pregnancy compared to younger women. Many of the complications...
Triple X syndrome is a genetic disorder in which a girl has three X chromosomes instead of two. Triple X occurs once in every 1,000 female births. However, doctors believe many girls with Triple X go their lifetime undiagnosed. The major...
Becoming a mother over the age of 40 carries with it some significant risks, including: infertility, miscarriage, birth defects and c-section delivery. The March of Dimes reports that despite those increased risks, most women go on to have healthy...
The International RadioSurgery Association says that brain cancer makes up 2 percent of cancers in the United States. One type of brain cancer is glioblastoma multiforme, a grade IV astroyctoma. Glioblastoma multiforme accounts for 50 percent of...
Medical experts believe alcoholism stems from a combination of genetic and environmental factors. A strong genetic contribution to alcoholism shows in the three- to four-fold higher risk for alcoholism among first-degree relatives of an alcoholic...
Although a person may appear physically fit and trim on the outside, she may be dealing with serious health issues on the inside. Monogenic and multifactorial inheritance disorders such as mental illness, alcoholism, diabetes and heart disease...
A surprising fact about genetics is that there are many syndromes that are termed "genetic," but have not been inherited from a parent. When DNA is passed from one generation to the next, it is copied. Generally, DNA is copied faithfully, however...
Congenital heart disease refers to problems in the structure and function of the heart because of abnormal heart development before birth. The U.S. National Library of Medicine notes that congenital heart disease is the most common type of birth...
Imagine a time when the health of your child was a complete mystery until the day of delivery. Amniocentesis was first developed in the late 1950s as a way of determining the sex of a child but was not used until the 1970s for the diagnosis of...
Down syndrome, a genetic defect that is beyond the control of the parent, occurs when there is an extra copy of the 21st chromosome in all or some of the cells in your body. Chromosomes are structures made from your unique DNA or genetic...
When prenatal screening identifies features of a genetic syndrome or there is a family history of genetic disease, a woman's health care provider may suggest prenatal genetic testing. Baby's DNA, obtained by chorionic villus sampling--commonly...
Parents once had to rely exclusively upon old wives tales regarding the size and shape of a mom-to-be's belly or her degree of morning sickness to give them clues to their unborn baby's gender. Modern science allows many parents to find out the...
Genetics is the process in which parents pass certain genes onto their children. An abnormal gene that is passed down through the family may have only minor consequences, or it may have a dramatic impact on one's quality of life. Abnormal genes...
Intersex problems, such as pseudohermaphroditism, true hermaphroditism or complex intersex disorders, may present at birth with clinical signs of ambiguous genitalia or may develop later as hormonal insufficiencies during puberty. Historically,...
The U.S. National Library of Medicine's Genetics Home Reference website says Triple X Syndrome, also known as Trisomy X or Trisomy 47, is a genetic condition where females have three X chromosomes instead of two. The European Journal of Human...
Obstetricians consider women over age 35 to be of "advanced maternal age." But more women over age 35 are getting pregnant---one in five first time new moms is over 35, the March of Dimes states. While it's still quite possible to get pregnant...
Genetic diseases are caused by defects in genes, segments of DNA that govern specific characteristics in a person. Common genetic disorders such as cystic fibrosis or Huntington's disease aren't always inherited, but may occur as a spontaneous...
Down syndrome, a congenital chromosomal disorder that causes physical anomalies and developmental delays, affects approximately 1 in 700 to 800 people, the Mayo Clinic reports. People with Down syndrome have an extra copy of chromosome number 21....
A child born with Ataxia-Telangiectasia will appear to develop normally for the first two years of life, but then delayed development of motor skills will become increasingly apparent. The child may begin to exhibit poor balance, impaired speech...
While embryos are male or female from the day of conception, gender isn't obvious on ultrasound until at least 12 weeks, and more often 16 to 20 weeks, Dr. Joseph Woo of Hong Kong states in Obstetric Ultrasound. Male and females fetuses have...
Down syndrome is a genetic disorder that causes mental retardation. Down syndrome is the most common genetic cause of severe learning disabilities in children. Learn about the different causes, symptoms, and treatments of down syndrome in this video.
