31 terms

Inheritance Patterns and Human Genetics

sex chromosome
one of the pair of chromosomes that determine the sex of an individual
any chromosome that is not a sex chromosome
sex-linked trait
a trait that is determined by a gene found on one of the sex chromosomes, such as the X chromosome or the Y chromosome in humans
linked gene
one of a pair of genes that tend to be inherited together
chromosome map
a diagram of gene positions on a chromosome
map unit
in chromosome mapping, an increment of 1 percent in the frequency of crossing-over
germ-cell mutation
mutation that occurs in an organism's gametes
somatic-cell mutation
a mutation that occurs in a body cell
lethal mutation
a gene or chromosomal mutation that influences the development of an organism in such a way that the organism cannot survive
the loss of a part of DNA from a chromosome
a reversal in the order of the genes, or of a chromosome segment, within a chromosome
the movement of a segment of DNA from one chromosome to another, which results in a change in the position of the segment; also the movement of soluble nutrients from one part of a plant to another
the failure of homologous chromosomes to separate during meiosis I or the failure of sister chromatids to separate during mitosis or meiosis II
point mutation
a mutation in which only one nucleotide or nitrogenous base in a gene is changed
a mutation in which a nucleotide or a codon in DNA is replaced with a different nucleotide
frameshift mutation
a mutation, such as the insertion or deletion of a nucleotide in a coding sequence, that results in the misreading of the code during translation because of a change in the reading frame
insertion mutation
a mutation in which one or more nucleotides are added to a gene
a diagram that shows the occurrence of a genetic trait in several generations of a family
in genetics, an individual who has one copy of a recessive autosomal allele that causes disease in the homozygous condition
genetic disorder
an inherited disease or disorder that is caused by a mutation in a gene or by a chromosomal defect
describes a characteristic that is influenced by many genes
complex character
a character such as skin color that is influenced strongly by both genes and the environment
multiple allele
more that two alleles for a genetic trait
a condition in which both alleles for a gene are fully expressed
incomplete dominance
one allele is not completely dominant over the other allele
sex-influenced trait
an autosomal trait that is influenced by the presence of male or female sex hormones
Huntington's disease
a rare hereditary disease of the brain characterized by involuntary movements of the limbs or face, decreasing mental abilites, and eventual death
a procedure used in fetal diagnosis in which amniotic fluid is removed from the uterus of the pregnant woman
chorionic villi sampling
a procedure in which the chorionic villi to are analyzed to diagnose fetal genotypes
genetic counseling
the process of testing and informing potential parents about their genetic makeup and the likelihood that they will have offspring with genetic defects or hereditary diseases
gene therapy
a technique that places a gene into a cell to correct a hereditary disease or to improve the genome