chromosomal diseases
It is estimated that 50% of spontaneous abortuses during the early months of gestation have a demonstrable chromosomal abnormality; there are, in addition, numerous smaller detectable errors and many others still beyond our range of identification. About 1% of all newborn infants possess a gross chromosomal abnormality.
Types
numerical chromosomal anomalies
- ploidy anomalies (aneuploidy)
- triploidy
- tetraploidy
- autosomal monosomies
- autosomal trisomies
- trisomy 21 (Down syndrome)
- trisomy 13
- trisomy 18
- trisomy 8
- trisomy 9
- autosomal tetrasomies
structural chromosomal anomalies
- deletions
- chromsome 13 deletion
- 18q- syndrome (del18q)
- 18p- syndrome (del18p)
- 4p- syndrome (del4p) (Wolf-Hischhorn syndrome)
- 5p- syndrome (del5p) (cat-cry syndrome)
- 11p- syndrome (del11p)
- 17p- syndrome (Miller-Dieker syndrome)
- isodicentric 22 (22pter-q11) (Schmid-Fraccaro syndrome)
- 21q- syndrome (del21q)
- 22q- syndrome (del22q)
chromosomal duplications
chromosomal recombinaisons
- recombinant chromsome 8 syndrome (RC8S)
chromosomal translocations
gonosomal anomalies
- monosomy X (45,X) (Turner syndrome)
- 47,XXY
- 47,XXX
- 47,XYY
mosaicism