Ultimately, BBS is distinguished from Laurence-Moon syndrome based on which genes are affected. However, one of the genetic mutations that cause BBS has also been found in individuals with Laurence-Moon syndrome, which illustrates the difficulty in distinguishing the two. There are 14 types of BBS, each of which is caused by a different genetic mutation. These 14 genes are BBS1, BBS2, ARL6 / BBS3, BBS4, BBS5, MKKS / BBS6, BBS7, TTC8 / BBS8, B1 / BBS9, C12ORF58 / BBS10, TRIM / BBS11, C4ORF24 / FLJ35630/BBS12, FLJ20345 / MKS1, and CEP290.
An ultrasound in pregnancy can be either done as a âroutineâ ultrasound, usually between 18-20 weeks or it is done for specific reasons which usually depend at the time of pregnancy. There are essentially three different types of ultrasounds, depending on how much information is required. 1  The limited ultrasound,
A common use of ultrasound in early pregnancy is to calculate a gestational age. For this purpose, an ultrasound is considered a highly accurate means of dating a pregnancy. In a normal pregnancy, the ultrasound results can provide an estimate of the gestational age to within five to seven days of accuracy. When a woman is having miscarriage symptoms, a doctor may order one or more ultrasounds to determine the viability of the pregnancy.